Professors Jain and Sochnikov received NSF research grant entitled “New Quantum Elastocaloric Demagnetization Refrigeration for the Millikelvin Range”. A major focus of their research will be the cooling of quantum chips. For this purpose, their teams will study ‘spin liquids’, which can be harnessed to achieve millikelvin temperatures without magnetic fields. At such low temperatures, […]
Associate Professor of Physics Menka Jain and the Institute of Materials Science is co-organizing a workshop-28th International Workshop on Oxide Electronics (IWOE) in Maine next month. The IWOE series has become an important venue to discuss recent advances and emerging trends in this developing field. The aim of the workshop is to provide an interdisciplinary […]
The James Webb Space Telescope released its first science observations on July 12 with much fanfare and excitement across the globe. UConn Physics Professor Jonathan Trump is part of the Cosmic Evolution Early Release Science collaboration that was awarded some of the first observations on the transformative new space telescope. Prof. Trump was interviewed by several local media outlets, […]
Professor Cara Battersby has been awarded an NSF CAREER grant! “The Faculty Early Career Development (CAREER) Program is a Foundation-wide activity that offers the National Science Foundation’s most prestigious awards in support of early-career faculty who have the potential to serve as academic role models in research and education and to lead advances in the […]
UConn is now home to tools that have played an instrumental role in mapping the universe — 10 large aluminum plates used as part of the Sloan Digital Sky Survey (SDSS). Measuring 32 inches across, one-eighth of an inch thick, and with thousands of tiny holes drilled in them, these plates may not be the […]
UConn’s collaboration with the Department of Defense Air Force Research Laboratory (AFRL) is launching a new project. It is titled Multiscale Modeling and Characterization of Metamaterials, Functional Ceramics and Photonics. This is a $4.7 M contract with $1M for Physics. The project’s goal is to explore and advance the understanding of electronic, photonic, magnetic, and […]
The article The Largest Suite of Cosmic Simulations for AI Training Is Now Free to Download; Already Spurring Discoveries describe research of a team of astrophysicists that includes UConn Professor of Physics Daniel Anglés-Alcázar. “Machine learning is revolutionizing many areas of science, but it requires a huge amount of data to exploit,” says Anglés-Alcázar. “The […]
UConn Physics Professor Jonathan Trump is part of a group of scientists who will be the first to conduct research using the James Webb space telescope. The local Fox News TV station conducted an interview with Prof. Trump.
On Friday December 3rd, a group of U.S. Senators, Richard Blumenthal (D-CT), Edward J. Markey (D-MA), Marco Rubio (R-FL), Elizabeth Warren (D-MA), and Rick Scott (R-FL) introduced a bipartisan a resolution to recognize the significant scientific, educational, and economic contributions made by the Arecibo Observatory telescope. “The telescope at Puerto Rico’s Arecibo Observatory was a […]
Chiara Mingarelli, Assistant Professor of Physics at UConn, is the lead researcher on a $650,000 Collaborative Research Grant from the National Science Foundation, half of which is earmarked for UConn, to conduct an experiment to prove the existence of supermassive black hole binaries. This grant will combine, for the first time, traditional astronomy with gravitational […]
UConn Physics graduate student Mohammed (Mo) Akhshik works on data gathered using the Hubble Space Telescope (HST) and has led to exciting discoveries, some while he served as the science Principle Investigator of the REQUIEM HST program from which he is co-author on two publications, one in Nature and one in Nature Astronomy. Akhshik is also […]
At the center of galaxies, like our own Milky Way, lie massive black holes surrounded by spinning gas. Some shine brightly, with a continuous supply of fuel, while others go dormant for millions of years, only to reawaken with a serendipitous influx of gas. It remains largely a mystery how gas flows across the universe […]
Prof. Emeritus Winthrop Smith and former student Prof. Douglas Goodman (Quinnipiac University) Edit Special Issue of Open Access Journal Atoms, on Low Energy Interactions between Ions and Ultracold Atoms The Special Issue of the online journal Atoms is a collection of current peer-reviewed articles by experts in the field of ultracold collisions and reactions involving […]
The Physics Department welcomes our newest faculty member, Dr. Anh-Thu Le, although he prefers to be called simply AT. AT worked for many years at the well-known James R. Macdonald Laboratory, rising to the rank of Research Professor. He worked alongside a world-known theorist, Dr. Chii-Dong Lin. Dr. Le went on to become an Assistant […]
Professor Andrew Puckett’s research group is currently leading, as part of a collaboration of approximately 100 scientists from approximately 30 US and international institutions, the installation in Jefferson Lab’s Experimental Hall A of the first of a series of planned experiments known as the Super BigBite Spectrometer (SBS) Program, with beam to Hall A tentatively […]
Physics major Nicole Khusid, a rising senior at UConn, was featured in a UConn Today article about her research. Nicole has been working on gravitional lensing of distant sources of gravitational waves, seeking to understand their multimessenger signals and detectability by future astrophysics facilities. Nicole was awarded a SURF (Summer Undergraduate Research Fund) award to […]
It seems that the muon, a heavier partner of the electron, may be breaking what have been understood as the laws of physics. The findings announced on April 7th were met with excitement and speculation at what this might mean. UConn physics researchers Professor Thomas Blum and Assistant Professor Luchang Jin helped pioneer the theoretical physics behind the findings.
Professor Cara Bettersby’s research is featured in the article “The Study of Big Data: How CLAS Researchers Use Data Science” published by UConn Today. Prof. Battersby’s work focuses on describing and studying the center of the Milky Way galaxy, which she calls an “experimental playground” for the distant cosmos. Her work described the spectroscopy of […]
New Physics PhD graduate Yasaman Homayouni is featured in a story on the class of 2021 from the College of Liberal Arts and Sciences (CLAS). For the full story of what inspired Yasaman and other students during their time at UConn, see the article in UConn Today.
Mark Rayner/CERN The Fermilab E989 experiment announced the first new result on the muon’s anomalous magnetic moment in almost 20 years. The new measurement, combined with Brookhaven’s E821, has increased the discrepancy with the Standard Model value to 4.2 standard deviations. UConn Professors Tom Blum and Luchang Jin explain the theory calculations in a feature […]
Professor of Physics Nora Berrah has been awarded the International Blaise Pascal Chaire d’Excellence, a prestigious honor whose previous winners include scientists and scholars from a wide range of disciplines, including multiple Nobel laureates. Her award was selected by a committee of scientists and voted on by the Permanent Commission Regional Council of the Région […]
UConn astrophysicist Chiara Mingarelli is part of a team of researchers who recently published data on a hint of a signal that sent ripples of excitement through the physics community. These monumental findings are the culmination of twelve and a half years of data gathered from NANOGrav — a network of pulsars across the galaxy — all in the hopes of detecting gravitational waves.
November 2, 2020 – Elaina Hancock – UConn Communications The Sloan Digital Sky Survey’s fifth generation – a groundbreaking project to bolster our understanding of the formation and evolution of galaxies, including the Milky Way – collected its very first observations on the evening of October 23. Image: The Sloan Digital Sky Survey’s fifth generation […]
UConn graduate student Gloria Fonseca Alvarez was featured with a video in the Author Interview series produced by the American Astronomical Society (AAS). In this video, Gloria talks about her work to understand the inner environments of black holes. The paper highlighted in the video shows that the orbits of emission-line gas around supermassive black holes are often smaller than expected from previous observations.
Most superconductors only work when they’re super cold. Chemists and metallurgists have experimented with different combinations of elements for years, trying to get superconductors that work at temperatures close to room temperature. Sochnikov and his students are thinking about it differently. What if mechanical changes such as squeezing or stretching could make a material a superconductor?
Erin Scanlon joins our Department in fall 2020 as Assistant Professor in Residence at the Avery Point Campus. Erin comes to UConn with an impressive track record of university teaching experience and scholarship in physics education research (PER). After earning a master’s degree in physics from Georgia Institute of Technology, Erin joined the faculty at […]
We are very excited to extend a warm welcome to a new UConn Physics Faculty member, Dr. Christopher Faesi. Chris is an astrophysicist, specializing in both observational work and modelling, primarily in the study of star formation. He got his PhD at Harvard University, followed by a postdoc at the Max Planck Institute for Astronomy […]
Kyungseon Joo, a professor of physics, has been named Chair of the CLAS Collaboration, one of the largest international collaborations in nuclear physics. CLAS involves 50 institutions from 9 countries and has about 250 collaborators. The collaboration recently completed the upgrade of the CEBAF Large Acceptance Spectrometer (CLAS12) for operation at 11 GeV beam energy […]
Assistant Professor of Physics Luchang Jin has been chosen to receive a prestigious Early Career Award from the US Department of Energy’s Office of High Energy Physics (HEP) for 2020. The amount of the award is $750,000 to be used over five years. The DOE Early Career Award is extremely competitive: this year only 16 scientists in […]
Jonathan Trump, Assistant Professor of Physics, will receive $738,090 over five years to compile a census of supermassive black holes in the universe. This will give insights into how supermassive black holes and galaxies evolve across cosmic time. Trump will also develop a bridge program for underrepresented undergraduate physics majors at UConn to increase their […]
Professors Tom Blum and Luchang Jin, along with colleagues at BNL and Columbia, Nagoya, and Regensburg universities have completed a first-ever calculation of the hadronic light-by-light scattering contribution to the muon’s anomalous magnetic moment with all errors controlled. The work is published in Physical Review Letters as an Editor’s Suggestion and also appeared in […]
A single x-ray can unravel an enormous molecule, physicists report in the March 17 issue of Physical Review Letters. Their findings could lead to safer medical imaging and a more nuanced understanding of the electronics of heavy metals. Medical imaging techniques such as MRIs use heavy metals from the bottom of the periodic table as …
The Geophysics research group (Prof. Vernon Cormier and students) operate a seismic wave station that continuously monitors vibrations in the earth’s crust, many of which arise from seismic events that happen far away. These waves travel through the deep earth, and eventually make their way to the surface where they are detected. The above […]
Could traveling into the past be part of our future? Quite possibly, says Ron Mallett, a UConn emeritus professor of physics who has studied the concept of time travel for decades. Earlier this month, he spoke with NBC Connecticut reporter Kevin Nathan about his life and work as a theoretical physicist, and discussed how time […]
The UConn Physics Department is delighted to announce that our 2019 Distinguished Katzenstein Lecturer will be Professor Dame Jocelyn Bell Burnell. Professor Dame Jocelyn Bell Burnell is world-famous for her discovery of pulsars in 1967. Pulsars are a special type of neutron star, the rotating dense remnant of a massive star. Pulsars have highly magnetic surfaces, and emit a beam of electromagnetic radiation […]
The Daily Campus published an article highlighting the research of Prof. Thomas Blum about Quantum Chromodynamics, a theory which describes the interactions between elementary particles. The development of this theory could help further understanding of the Standard Model of particle physics. The Standard Model is what physicists use to describe the fundamental building blocks of […]
UConn Astrophysicist and observational astronomer Jonathan Trump was a recent guest on UConn 360, a podcast from the Storrs campus of the University of Connecticut. In this conversation, Jonathan tells about how attending a lecture as an undergraduate at Penn State captured his interest and changed the course of his professional career. Now Jonathan offers […]
Physicists used to think that superconductivity – electricity flowing without resistance or loss – was an all or nothing phenomenon. But new evidence suggests that it’s not so clear cut, at least in copper oxide superconductors. “If we understood why copper oxide is a superconductor at such high temperatures, we might be able to synthesize a better one”, says UConn physicist Ilya Sochnikov. Sochnikov and his colleagues at Rice University, Brookhaven National Lab and Yale recently figured out part of that puzzle, and they report their results in the latest issue of Nature.
Daniel McCarron, assistant professor of physics, the College of Liberal Arts and Sciences, will receive $645,000 over five years for his work on the development of techniques to trap large groups of molecules and cool them to temperatures near absolute zero. The possible control of molecules at this low temperature provides access to new research applications, such as quantum computers that can leverage the laws of quantum mechanics to outperform classical computers.
When Carlos Trallero started his academic career in physics, he had no idea he would become a pioneer in a field of research that uses high-power lasers to investigate atomic and molecular physical phenomena. Originally from Cuba, where there isn’t much funding for experimental research, Trallero began his academic career by studying theoretical physics. But as a senior graduate student at Stony Brook University, he got the chance to work in a lab doing experimental work and quickly recognized it was his true passion.
May 27-June 5 UConn Physics Department hosted an international summer school Strong interactions beyond simple factorization: collectivity at high energy from initial to final state. The school was supported by an NSF grant to Prof. Kovner and was devoted to modern approaches to the physics of high energy hadronic and heavy ion collisions.
Amelia Henkel, graduating Double Major in Physics and Human Rights, and President of the Undergraduate Women in Physics Club, speaks on the CLAS website about her passion for physics and human rights, and how she mastered challenges in her remarkably interdisciplinary curriculum. “We really need to interact with other disciplines,” says Amelia, “because that’s […]
On April 11th and 12 of 2019 Prof. Paul Corkum of the Joint Attosecond Laboratory (University of Ottawa and the National Research Council of Canada) visited the department. Prof. Corkum’s main area of research is on the interaction of ultrashort laser pulses with matter broadly defined. His most notable contribution is perhaps the discovery of […]
The University of Connecticut’s Katherine Whitaker is part of a team of astronomers who have put together the largest and most comprehensive “history book” of the universe from 16 years’ worth of observations from NASA’s Hubble Space Telescope.This image, a mosaic of nearly 7,500 separate Hubble exposures, presents a wide portrait of the distant universe and contains roughly 265,000 galaxies that stretch back through 13.3 billion years to just 500 million years after the Big Bang.
UConn physics professor Nora Berrah has been elected to the historic and prestigious American Academy of Arts and Sciences. This year, more than 200 individuals were elected to the academy with compelling achievements in academia, business, government, and public affairs. Berrah, who was head of the physics department from 2014 to 2018, has been recognized […]
This image is the first ever taken of a black hole, captured by the Event Horizon Telescope (EHT) project. The black center is a direct view of the event horizon of a supermassive black hole with a mass of 6.5 billion times the Sun, lying at the center of the Virgo cluster of galaxies. The bright ring is emission from hot gas just above the event horizon, with an asymmetric shape caused by gravitational lensing of light in the strong gravity of the black hole. The EHT collaboration captured the image using a network of 8 radio telescopes that spanned the Earth.
The 2018 Reynolds lecture speaker was Prof Andrew Millis, a Professor of Physics at Columbia University and a co-Director of Center for Computational Quantum Physics at the Flatiron Institute. Dr. Millis’s research focus is theoretical condensed matter physics. He is the leading authority in theory of correlated materials, application of new theoretical ideas to actual […]
An international research team headed by Dr. Aaron LaForge from the research group of Prof. Nora Berrah in the Physics department at UConn has recently discovered a new type of decay mechanism leading to highly efficient double ionization in weakly-bound systems. The team has published its results in the science journal “Nature Physics”. Ionization is […]
Original UConn Today article here Rising Star in Astrophysics Receives Sloan Foundation Fellowship February 19, 2019 – Jessica McBride – Office of the Vice President for Research Kate Whitaker, assistant professor of physics, stands next to a telescope inside the observatory on top of the Gant Complex on Feb. 14, 2019. (Peter Morenus/UConn Photo) As […]
Physics professor Nora Berrah has been named a 2018 Fellow of the American Association for the Advancement of Science (AAAS). Prof. Berrah has been recognized for her distinguished contributions to the field of molecular dynamics, particularly for pioneering non-linear science using x-ray lasers and spectroscopy using synchrotron light sources. View full story on CLAS website.
A young Cara Battersby once scrawled out the phrase “Science is curious” in a school project about what she wanted to do when she grew up.
This simple phrase still captures Battersby’s outlook on her research about our universe.
Recently shortlisted for the 2018 Nature Research Inspiring Science Award, Battersby has been working on several projects aimed at unfolding some of the most compelling mysteries of galaxies near and far.
“I’m really interested in how stars are born,” Battersby says. “They’re the source of all life on Earth.”
Battersby is leading an international team of over 20 scientists to map the center of the Milky Way Galaxy using the Submillimeter Array in Hawaii, in a large survey called CMZoom. She was recently awarded a National Science Foundation grant to follow-up on this survey and create a 3D computer modeled map of the center of the Milky Way Galaxy.
Connor Occhialini – Finalist 2018 LeRoy Apker Undergraduate Achievements Award by Jason Hancock One of our star undergraduates, Connor Occhialini, has won national recognition as a finalist in the 2018 LeRoy Apker Undergraduate Achievements Award competition for his research in the UConn Physics department. The honor and distinction is awarded not only for the excellent […]
The Katzenstein Distinguished Lectures series continued in the 2018 academic year with its twenty second Nobel Laureate lecturer, with an October 26, 2018 lecture by Professor Rainer Weiss of the Massachusetts Institute of Technology. The title of Professor Weiss’ talk was “Exploration of the Universe with Gravitational Waves”, with abstract: The observations of gravitational waves […]
The Physics Nobel prize in 2018 was awarded to Gérard Mourou (École Polytechnique, Université Paris-Saclay), Arthur Ashkin (Bell Laboratories and Lucent Technologies), and Donna Strickland (University of Waterloo) for ground-breaking inventions in the field of laser physics.
Dynamic Quantum Matter, Entangled orders and Quantum Criticality Workshop, June 18- June 19, 2018, sponsored by UConn, NSF, Nordita, Villum Center for Dirac Materials, Institute for Materials Science. The conference focused on entangled and non-equilibrium orders in quantum materials.
Physics major Brenna Robertson has been selected as the recipient of the 2018 Mark Miller Undergraduate Research Award. Brenna’s proposal, which focuses on modeling supermassive black hole spin using spectral emission diagrams, was selected from among a strong pool of applicants. Brenna Robertson is working with Prof. Jonathan Trump. The Mark Miller Award is a […]
Undergraduate Physics Majors, Sam Cutler and Anthony (Josh) Machado, recently received awards from the NASA Connecticut Space Grant Consortium. Sam was awarded an Undergraduate Research Fellowship to perform research at UConn this summer working with Prof. Kate Whitaker. The title of his research project is “Examining High Redshift Rotation Curve Outside the Local Universe”. Josh […]
The Physics Department Graduate Student Association, in collaboration with the faculty, organized the Annual Research Poster Day which was held this year on March 23, 2018. About 15 students presented their research in a poster presentation. Awards were presented to graduate students Erin Curry and Martin Disla, and an undergraduate student Sadhana Suresh.
Prof Alan Wuosmaa has been awarded a grant for 3 years for Studies of exotic nuclei with transfer reactions. For the information about Prof. Wuosmaa research visit his home page.
Professor Tom Blum has been selected a “Fermilab Distinguished Scholar”. Fermilab Distinguished Scholars are rotating multi-year appointments for U.S. theorists in either the Fermilab Theoretical Physics Department or the Theoretical Astrophysics Group. The Fermilab Distinguished Scholars program aims to: Strengthen connections between the Fermilab Theoretical Physics and Astrophysics groups and the wider U.S. particle-theory community. […]
Professor Vernon F. Cormier from the Department of Physics, University of Connecticut has received a grant from the National Science Foundation to study the transition from liquid to solid in the Earth’s core using seismic wave measurements. Cormier’s project will determine the structure of the Earth’s inner core in relation to the processes that […]
Monday, March 26, 2018 The 21st Annual Katzenstein Distinguished Lecture was hosted by the UConn Physics Department, featuring Dr. Takaaki Kajita, 2015 Nobel Prize Winner from the University of Tokyo, speaking on “Oscillating Neutrinos.” After the lecture, a banquet with the speaker was held for members and guests of the department. We enjoyed welcoming alumni and […]
PhD student Lukasz Kuna and undergraduate Hope Whitelock participate in a symposium “Mesoscopic phenomena in ceramic materials” arranged by Materials Scientist Serge Nakhmanson at the “Electronic and Advanced Materials Conference” in Orlando, Florida. Four UConn students including Tulsi Patel, Krishna Chaitanya Pitike, Lukasz Kuna and Hope Whitlock showcased their research.
Professor Carlos Trallero has been granted $1.06 million from the Department of Defense, the U.S. Air Force and the Air Force Office of Scientific Research to study recollision physics at the nanoscale to help develop ultrafast electronics. This research will enhance the knowledge base of electron recollision dynamics at the nanoscale, which can be used to develop ultrafast light-driven electronics.
An artist’s rendering of hot material falling into a supermassive black hole, creating what is called the accretion disk, shown in orange. Reverberation mapping measures the time it takes light to travel between two areas of the accretion disk. The ‘light echo’ enables direct measurement of the mass of the black hole. This reverberation mapping […]
Muon g-2 Theory Initiative Hadronic Light-by-Light working group workshop
Workshop participants will discuss recent progress and plans to determine the hadronic light-by-light scattering contribution to the muon anomalous magnetic moment, which is expected to contribute the largest uncertainty in the Standard Model prediction. The goal of the workshop is to estimate current and expected systematic errors from lattice QCD, dispersive methods, and models and create a plan to address them in time for new experiments at Fermilab and J-PARC.
December 19, 2017 – Colin Poitras – UConn Communications Scientists from three major research universities successfully manipulated the outcome of a chemical reaction and, in doing so, created a rare molecular ion. Through a process known as “controlling chemistry,” the researchers bonded an oxygen atom to two different metal atoms, creating the barium-oxygen-calcium molecular ion or BaOCa+ The same […]
Two UConn physics professors will be among the world’s first scientists to explore the universe using the new James Webb Space Telescope. The highly competitive, peer-reviewed James Webb Space Telescope Early Release Science program was created to test the capabilities of the new observatory and to showcase the tools the telescope is equipped with. Of more than 100 proposals submitted, only 13 were chosen to participate in the early release phase, including two separate proposals involving UConn researchers Kate Whitaker and Jonathan Trump, both assistant professors of physics.
Solving the complex problems that we face in our world today requires a more talented workforce than we have ever needed before. Such a workforce must be comprised of a wide range of diverse talents and creative insights. No segment of the population can be ignored or overlooked in this talent search. This presentation will describe the most recent research that demonstrates the positive impact that social and informational diversity has on science and innovation, the reasons for this impact and the importance of committed leadership in achieving a strong and inclusive workplace where creativity and productivity is maximized.
The American Physical Society (APS) has named two UConn Physics faculty as APS Fellows. APS Fellowship is a distinct honor signifying recognition by one’s professional peers and is an honor bestowed by election. The criterion for election is exceptional contributions to the physics enterprise; e.g., outstanding physics research, important applications of physics, leadership in or service to physics, […]
In May, 2017 UConn alumnus Alex Barnes was awarded a postdoctoral fellowship in Nuclear Physics at Carnegie Mellon University, working in the group of Prof. Curtis Meyer. Alex begins this appointment immediately after completing his PhD at the University of Connecticut in April 2017, under the guidance of Prof. Richard Jones. In his new position, […]
The U.S. Centers for Disease Control lists radon as a primary cause of lung cancer, second only to smoking. The Environmental Protection Agency estimates that 20,000 deaths each year from lung cancer in the U.S. are the result of exposure to radon in the living environment. It is believed that as many as 1 in […]
As a research assistant in the physics department at UCONN, I assisted in the alignment, maintenance, and principles of operation of the various apparatuses and measurement techniques used within cold atomic, molecular, and optical (AMO) experimental physics research. This included optical components, laser alignment, laser locking, saturation absorption spectroscopy, and electrodynamic ion trapping. Some specific […]
Attached is our record for the Mw 6.9 earthquake associated with eruptions of the Kilauea volcano on the big island of Hawaii. The large waves arriving after 2300 GMT are surface waves (elastic energy that exponentially decays with depth away from the surface) traveling from the earthquake to us. The beating pattern is characteristic of […]
Scientists have been rigorously commissioning the experimental equipment to prepare for a new era of nuclear physics experiments. This equipment is at the newly upgraded Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab in Newport News, Virginia. These activities have already led to the first scientific result. This research demonstrates the feasibility of detecting a potential new kind of particles known collectively as exotic hadrons. The existence and spectrum of these new particles hold important clues to unlocking the mystery of “quark confinement” — why no quark has ever been found alone.
As a theoretical physicist studying the fundamental elements of matter, UConn graduate student Daniel Hoying creates calculations so large and complex they require supercomputers to perform them. So Hoying is obviously excited that he will soon have regular access to one of the world’s most powerful supercomputers at the U.S. Department of Energy’s Brookhaven National […]
For the first time, scientists have directly detected gravitational waves — ripples in space-time — in addition to light from the spectacular collision of two neutron stars. This marks the first time that a cosmic event has been viewed in both gravitational waves and light. The discovery was made using the U.S.-based Laser Interferometer Gravitational-Wave […]
Instead of directly searching for new particles as the LHC experiments are doing in Geneva, the muon g-2 experiment at Fermilab measures a well-known physical property of the muon to ever greater precision, looking for deviations from the value it should have based on the Standard Model of particle physics, assuming that no new forces […]
The Katzenstein Distinguished Lectures series continued in Fall 2016 for its 19th year, with an October 28, 2016 lecture by Professor Leon N. Cooper of Brown University, entitled “On the Interpretation of the Quantum Theory: Can Free Will And Locality Exist Together In The Quantum Theory?” Professor Cooper shared the 1972 Nobel Prize in Physics […]
Whoever said rules were made to be broken wasn’t a physicist. When something doesn’t act the way you think it should, either the rules are wrong, or there’s new physics to be discovered. Which is exactly what UConn’s Connor Occhialini ’18 (CLAS), an honors student majoring in physics and math, found when he began researching scandium fluoride. Most materials swell as they heat up. Scandium fluoride must be doing something else, reasoned Occhialini. […]
John Mangeri’s Award Lands Him in Argonne National Laboratory John Mangeri (left) with his SCGSR-award host Dr. Olle Heinonen (right) in front of the Chemistry building (bldg. 200) at Argonne National Laboratory. (Photo credit to Dr. Andrea Jokisaari) By Katherine Eastman John Mangeri, a Ph.D. candidate in Dr. Serge Nakhmanson’s “Complex Materials by Computational Design” […]
Researchers working with the Continuous Electron Beam Accelerator Facility (CEBAF) at the U.S. Department of Energy’s Jefferson National Accelerator Facility (J-Lab) have published their first scientific results since the accelerator energy was increased from six billion electron volts (GeV) to 12 GeV. The upgrade was commissioned to enable the next generation of physics experiments that will allow scientists to see smaller bits of matter than have ever been seen before. The first publication from the upgraded CEBAF was published by the GlueX collaboration in the April issue of Physical Review C.
The American Physical Society (APS) has named three UConn Physics faculty as APS Fellows. APS Fellowship is a distinct honor signifying recognition by one’s professional peers and is an honor bestowed by election. The criterion for election is exceptional contributions to the physics enterprise; e.g., outstanding physics research, important applications of physics, leadership in or […]
Dr. Sochnikov is a recipient of Montana Instruments Cold Science Exploration Awards Lab Startup Grant. Dr. Ilya Sochnikov has just started new scanning SQUID microscopy lab at the University of Connecticut. Ilya Sochnikov’s research focuses on nanoscale quantum phenomena in new materials. An emergence of a new phenomenon or a phase transition occurs when interactions […]
October 6, 2015 – Kim Krieger – UConn Communications Jason Hancock, Assistant Professor in Physics, with graduate students, Erin Curry and Sahan Handunkanda, have been investigating a substance that shrinks when it warms. Most materials swell when they warm, and shrink when they cool. But UConn physicist Jason Hancock has been investigating a substance that responds in reverse: […]
March 26, 2015 – Tim Miller Researchers have made an experimental breakthrough in explaining a rare property of an exotic magnetic material, potentially opening a path to a host of new technologies. From information storage to magnetic refrigeration, many of tomorrow’s most promising innovations rely on sophisticated magnetic materials, and this discovery opens the door to harnessing […]
Prof. Philip Mannheim, Department of Physics, University of Connecticut
Why there are dark matter, dark energy, and quantum gravity problems, and what we can do about them
We trace the origin of the dark matter, dark energy and quantum gravity problems to the extrapolation of the standard Newton-Einstein wisdom to beyond its solar system origins. We show that this same solar system wisdom can be obtained from the conformal gravity theory, with its extrapolation leading to a resolution of all of the dark matter, dark energy and quantum gravity problems.
Electronic pseudogap from fluctuations in low dimensional materials
Most metal-to-insulator and metal-to-superconductor transitions are so dramatic that certain symmetries are also concurrently broken, and an energy gap opens in lockstep with this process. But there are electronic systems that develop energy gaps without any broken symmetry, most notably the “pseudogap” in cuprate superconductors. In this talk, I will show two examples of electronic pseudogap in unexpected places: the heavily hole-doped cuprates [1], and an excitonic insulator candidate Ta2NiSe5 [2]. The former is supposedly a good metal where mean-field BCS is thought to apply, and the latter is a structural symmetry-breaking system with strong electron-phonon coupling. Via angle-resolved photoemission spectroscopy and x-ray scattering, we show the electronic gap to persist well above the transition temperature in both systems. With insights from controlled numerical calculations, we show that fluctuation is an important factor when describing the properties of low dimensional material systems. Finally, I will discuss a few new directions in the study of fluctuations.
[1] Phys Rev X 11, 031068 (2021); Nat Mater 22, 671 (2023)
Dr. Shafique Adam, Washington University in St. Louis
A narrow magic window for ultraflat bands and emergent heavy fermions near the magic angle in twisted bilayer graphene
The notion of a single “magic angle” in twisted bilayer graphene has evolved into a fascinating array of magic angles and ranges each describing different facets of the material’s behavior. While the original continuum model predicted a nominal magic angle, its simplicity ignored the intricate interplay of different physical phenomena. For example, lattice relaxation [1] near the magic angle shifts its value upward, only to be counteracted by pseudomagnetic fields. Including a symmetry allowed relaxation parameter changes this magic angle to a magic range. Yet another magic angle emerges from the coupling to phonons when the Fermi velocity equals the phonon sound velocity. Building upon this rich tapestry of magical effects, we will discuss our recent work on the convergence of lattice relaxation and Hartree interaction near the magic angle [2]. We unveil a previously unreported Lifshitz transition to a Fermi surface topology that supports a “heavy fermion” pocket and an ultraflat band pinned to the Fermi energy. Analytical and numerical insights shed light on the narrow “magic angle range” where the “heavy fermion” is stable and make predictions for its experimental observation. We believe that the bands presented here are accurate at high temperature and provide a good starting point to understand the myriad of complex behavior observed in this system.
[1] “Analytical Model for Atomic Relaxation in Twisted Moiré Materials” by MMA Ezzi, GN Pallewela, C De Beule, EJ Mele, and S Adam, arXiv:2401.00498 (2024)
[2] “A self-consistent Hartree theory for lattice-relaxed magic-angle twisted bilayer graphene” by MMA Ezzi, L Peng, Z Liu, JHZ Chao, GN Pallewela, D Foo, and S Adam arXiv:2404.17638 (2024)
ASTRA: A Transition-Density-Matrix Approach to Time-Resolved Molecular Ionization
Attosecond science, which investigates the time-resolved correlated motion of electrons in atoms, molecules, and solids, is rapidly advancing toward larger molecular systems and more complex processes, such as multiple ionization and molecular fragmentation. Theoretical methods capable of addressing both multiple excitations and photofragment entanglement are essential to capture these phenomena. Among the most promising theoretical approaches are ab initio wave-function-based close-coupling (CC) methods, increasingly adopted by the AMO community.
Despite significant progress from codes like XCHEM [1,2], tRecX [3], RMT [4], and UKRmol+ [5], scaling remains a major challenge – whether in handling ionic correlation, accounting for many atoms, or for distant fragments. To address these limitations, we developed ASTRA [6] (AttoSecond TRAnsitions), an ab initio CC molecular ionization code based on high-order transition density matrices between correlated ionic states of arbitrary multiplicity [7], and hybrid Gaussian-B-spline integrals [5,9]. ASTRA integrates multiple state-of-the-art codes, such as DALTON [8], a general-purpose quantum chemistry code, LUCIA [7], a large-scale CI code, and GBTOlib [5], a hybrid integral library suited for slow photoelectrons and comparatively small molecules.
ASTRA has successfully reproduced total and partial photoionization cross sections, photoemission asymmetry parameters, and molecular-frame photoelectron angular distributions for molecules such as N 2 , CO, H 2 CO, and Pyrazine, showing excellent agreement with existing benchmarks. Currently, ASTRA is being applied to study attosecond transient absorption spectra of CO and O 2 , as well as sequential XUV-pump IR-probe ionization of C 2 H 4 . Its formalism naturally extends to molecular double ionization and can efficiently model electron exchange between multiple disjoint molecular fragments − relevant for describing ionization in weakly bound clusters like (H 2 O) n .
Looking ahead, continued integration with tools tailored to high-energy photoemission, non-adiabatic nuclear dynamics, and strong fields ionization will be critical for addressing emerging challenges in ultrafast many-body dynamics. Free-electron lasers enable time-resolved studies of core ionization, while table-top attosecond pump-probe experiments are targeting increasingly larger molecules, monitoring both electron dynamics and nuclear rearrangements throughout chemical reactions with intense probe pulses [10]. To reproduce these complex experiments, we are collaborating with NIST to replace GBTOlib with a more efficient hybrid library capable of handling larger molecules and higher orbital angular momenta. We are also pairing ASTRA with surface-hopping methods [11], where multiphoton ionization is typically not available. Additionally, to track the asymptotic evolution of weakly coupled photofragments under strong light fields − without incurring prohibitive computational costs − we are considering integrating separate optimized propagators for each fragment, which will open the door for us to simulate strong-field multichannel molecular-ionization processes.
[1] M. Klinker et al., J. Phys. Chem. Lett. 9, 756 (2018).
[2] V. J. Borràs et al., Science Advances 9, eade3855 (2023).
[3] A. Scrinzi, Comput. Phys. Commun. 270, 108146 (2022).
[4] A. C. Brown et al., Comput. Phys. Commun. 250, 107062 (2020).
[5] Z. Masin et al., Comp. Phys. Commun. 249, 107092 (2020).
[6] J. M. Randazzo et al., Phys. Rev. Res. 5, 043115 (2023).
[7] J. Olsen et al., J. Chem. Phys. 89, 2185 (1988); ibid. 104, 8007 (1996).
[8] K. Aidas et al., Comp. Mol. Sci. 4, 269 (2014).
[9] H. Gharibnejad et al., Comp. Phys. Commun. 263, 107889 (2021).
[10] F. Vismarra et al., Nature Chemistry (2024).
[11] L. Fransén et al., J. Phys. Chem. A 128, 1457 (2024).
Jacob Heeren is a data analyst at Collins Aerospace, where he supports both commercial and military operations. His responsibilities span the entire data pipeline, encompassing data engineering, visualization, analytics, and governance across diverse projects. He holds degrees in psychology and applied mathematics from Iowa State University, with additional studies in astrophysics at the University of Iowa. Outside of his professional role, Jacob enjoys rock climbing and creating music, reflecting his passion for both physical and creative pursuits. Jacob will discuss his career path, current role, and useful skill sets for data science positions
Román Fernández Aranda, Department of Physics, University of Crete and FORTH Institute of Astrophysics, Greece
A Burning Hot DOG: The extreme ISM conditions of the most luminous obscured galaxy in The Universe
Hot dust-obscured galaxies (or Hot DOGs) are a remarkable population of high-redshift galaxies. Hot DOGs harbor hyper-luminous supermassive black holes (SMBHs), which are believed to provide strong feedback, creating extreme conditions in the interstellar medium (ISM) of their host galaxies in recurrent episodes of strong accretion and heavy obscuration. W2246-0526 is a Hot DOG at redshift 4.6 and the most luminous obscured galaxy known to date. I will present ALMA observations of both the brightest far-IR fine-structure emission lines and their underlying dust continuum, combined with ISM modeling of the gas and the dust. This work sheds light on the extreme conditions galaxies can experience during the early stages of the Universe, which is critical to our understanding of how distant and young galaxies evolve.
Arrays of dipolar-interacting spins - magnetic atoms, polar molecules, and Rydberg atoms - represent powerful and versatile platforms for analog quantum simulation experiments. The internal state dynamics in these dipolar arrays provide a natural setting to explore problems of equilibrium and non-equilibrium quantum magnetism. The presence of many internal states of the atoms and molecules further enables studies of large-spin magnetism, but also holds promise for more general quantum simulation studies. Here we describe how the simple addition of multi-frequency microwave fields to Rydberg arrays enables highly controllable studies of few- and many-body dynamics along an internal-state “synthetic” dimension. I’ll discuss several early studies in the Rydberg synthetic dimension platform, touching on interaction-driven phenomena relevant to topology, artificial gauge fields, and disorder-induced localization. Looking forward, such microwave manipulation opens up several new directions for exploring complex, driven quantum matter in dipolar arrays.
Structured Light and Induced Vorticity in Superconductors
Questions of controlling the quantum states of matter via light have been at the forefront of research on driven phases. We demonstrate the effects of imprinted vorticity on superconducting coherent states using structured light. Within the framework of the generalized time-dependent Ginzburg-Landau equation, we show the induction of coherent vortex pairs moving in phase with electromagnetic wave oscillation. The structured light, generated by a Laguerre-Gaussian beam, provides light sources with various quantum properties, such as spin angular momentum and orbital angular momentum. This state of light is also well known as an optical vortex, characterized by a twisted phase front. In the current work, we investigate the optically induced dynamics of superconducting coherent states using both normal light sources and optical vortices. These results uncover rich hydrodynamics of superconducting states and suggest new optical applications for imprinting quantum states on superconducting materials.
How to Make a Faster Trapped-Ion Quantum Computer?
Trapped ions offer a pristine platform for quantum computation, but enhancing the interactions without compromising the qubits remains a crucial challenge. In this talk, I will present a strategy to enhance the interaction strengths in trapped-ion systems via parametric amplification of the ions’ motion, thereby suppressing the relative importance of decoherence. We illustrate the power of this approach by showing how it can improve the speed and fidelity of two-qubit gates in multi-ion systems and how it can enhance collective spin states useful for quantum metrology. Our proposal has been further demonstrated in the experiment, confirming the enhancement. Our results open a new avenue of phonon modulation in trapped ions and are directly relevant to numerous other physical platforms in which spin interactions are mediated by bosons.
Dr. Eric Koch, Harvard Smithsonian Center for Astrophysics
Revealing the multi-phase neutral interstellar medium’s role in the star formation lifecycle: a sharpened view of nearby galaxies from LGLBS and PHANGS-JWST
The neutral interstellar medium (ISM) fuels the star formation lifecycle, yet we still lack vital constraints on the formation and destruction of molecular clouds because of challenges in observing the cold neutral ISM phases with high resolution and sensitivity. With dedicated surveys, the combination of VLA, ALMA, and JWST can now make significant advances in the coming years. In this talk, I will present multiple observational approaches that are making progress in this area: detailed 21-cm HI VLA mapping across the Local Group from the Local Group L-band Survey (lglbs.org), resolved molecular cloud studies with ALMA and JWST in M33 and PAH imaging from PHANGS-JWST as a highly sensitive resolved view of the total neutral gas tracer (phangs.org). These surveys bridge Galactic with extragalactic star formation studies and provide new constraints to guide the next generation of numerical simulations.
Bi-polaron superconductivity in the low density limit
It has been assumed for decades that high values of Tc from the electron-phonon coupling are impossible. At weak-to-intermediate coupling strength this result follows from the Migdal-Eliashberg theory, while at strong coupling, when bipolarons form, the transition temperatures are low because of the exponential effective mass enhancement. However, the latter conclusion was based on numerical solutions of the Holstein model. I will discuss a different model with coupling based on the displacement modulated hopping of electrons and argue that much larger values of the bipolaron Tc can be achieved in this setup. Non-locality of the problem gives rise to small-size, yet relatively light bipolarons, which can be studied by an exact sign-problem-free quantum Monte Carlo approach even in the presence of strong Hubbard and Coulomb potentials. We find that Tc in this model generically and significantly exceeds typical upper bounds based on Migdal-Eliashberg theory or superfluidity of Holstein bipolarons, and, thus, offers a route towards the design of high-Tc superconductors via functional material engineering. Finally, there are indications for even better prospects in systems with non-linear electron-phonon coupling.
Cortex Fusion Systems, Inc. uses shaped ultrafast laser pulses to catalyze fusion reactions in molecules. Our work comprises (1) designing transiently confining effective one-electron potentials in field-dressed molecules, (2) performing quantum chemistry calculations to validate the enhancement of nuclear tunneling by laser-modified electron screening dynamics, and (3) testing pulse shapes in the laser lab by coupling ultrafast spectroscopy techniques with nuclear radiation detection and spectrometry. In this regard, “quantum-controlled fusion” is a coherent, under-the-barrier process that does not require plasma ignition. Our goal is to repurpose the modern suite of commercial femtosecond laser amplifiers and pulse-shaping techniques to achieve compact and scalable fusion generators using quantum control.
Monica Vidaurri, Stanford University and NASA Goddard
Ethics and Aliens: the need for an ethical approach to space science
The progress of space science and exploration has seemingly inevitably fallen to private companies, to the concern of private citizens and scientists, who are directly impacted by private actions in space. Additionally, academia has reached a critical limit in terms of unchecked features that promote elitism and exclusionism, including increasingly competitive admissions to programs and fellowships, scarcity in jobs, prevalent sexual harassment, and others. As individuals, it is difficult to imagine what a truly ethical framework for our work looks like, let alone how we alone can influence laws and policy to change the actions of individuals with seemingly unlimited wealth and resources. This talk will introduce 3 main facets of what ethics means with respect to space science and exploration, including introducing space science as a historically oppressive institution, and how we can begin to move past this as individuals, labs, departments, and institutions. The norms we allow and ignore ultimately shape these broader laws, policies, and workplace culture. As a result, our science cannot be detached from the social and political framework it exists in, and the custom of early and regular collaboration with ethicists and planetary protection specialists (and other social scientists) is critical for not only mission safety, but mission and science integrity, as well as the well-being of those contributing to the mission and who gets to be included in such work. Creating a safe, responsible, and ethical space for peaceful purposes cannot wait for the international space community to create these practices de jure, but must be started at the individual level and regarded as custom for integration into international law, de facto, and require an uncomfortable self-assessment in the true goals of space science, as well as the ways that the academic structure has failed certain groups of students. By creating a new framework that prioritizes ethics, only then can we responsibly go into the unknown.
Unveiling the Physics of Galaxy Formation and its Large-Scale Effects at Cosmic Dawn
Cosmic Dawn, loosely defined here to be the first billion years of cosmic time, is an ever-intriguing era that witnessed the formation of the first generations of galaxies. Toward the end of it there was also the last major phase transition of our Universe, the epoch of reionization (EoR), which is believed to be driven by the hydrogen-ionizing background emerged from the early galaxies formed. In this talk, I will explain how Cosmic Dawn becomes a real exciting epoch for unveiling the physics of galaxy formation thanks to the James Webb Space Telescope (JWST), as well as several forthcoming facilities such as SPHEREx, Roman Space Telescope, Square Kilometer Array, and LiteBIRD focusing on the large-scale effects. I will discuss the theoretical landscape galaxy formation at Cosmic Dawn informed by new JWST observations, with a particular focus on the phenomenon of bursty star formation. I will introduce methods and ideas to shed light on different aspects of early galaxy formation, including the star formation history, stellar feedback, outflows, and the ionizing output, using both individual galaxies and their effects on the large-scale structure and cosmic background radiations. With a few case studies, I will demonstrate how to harness the power of the aforementioned facilities and their synergies for these purposes.
We discuss the anharmonic oscillator in quantum mechanics using exact WKB methods in a ‘t Hooft-like double scaling limit where classical behavior is expected to dominate. We compute the tunneling action in this double scaling limit, and compare it to the transition amplitude from the vacuum to a highly excited state. Our results, exact in the semiclassical limit, show that the two expressions coincide, apart from an irreducible and surprising instanton contribution. The semiclassical limit of the anharmonic oscillator betrays its quantum origin as a rule showing that the quantum theory is intrinsically gapped from classical behavior. Besides an example of a resurgent connection between perturbative and nonperturbative physics, this may provide a way to study transition amplitudes from tunnelling actions, and vice versa.
Dr. Esteban Goetz, Department of Physics, University of Connecticut
Interferometric Harmonic Spectroscopy for Electron Dynamics Imaging and Attosecond Pulse Train Phase Characterization
The advent of ultrashort light pulses has opened the possibility of investigating atomic and molecular processes on their natural time scales. In particular, Attosecond Transient Absorption Spectroscopy (ATAS) [1], a technique that allows to time-resolve the quantum dynamics of electrons by monitoring the absorption of extreme ultraviolet (XUV) radiation by an atomic or molecular system when the latter is dressed by an infrared (IR) laser source.
Motivated by recent experimental advances in self-referenced interferometric harmonic spectroscopy [2], we theoretically investigate an alternative approach to ATAS for electron dynamics imaging and attosecond pulse train (APT) phase characterization. In contrast to ATAS, which gives access to the imaginary part of the refractive index through an absorption measurement, an interferometric phase measurement gives information of its real part. In this talk, I will discuss the link between the XUV phase measurements of Ref. [2] and the different photoexcitation pathways occurring at the atomic level which are imprinted in the real part of the macroscopic refractive index. As an application, we show how such an interferometric approach can be used for phase retrieval of attosecond pulse trains based on two-arm harmonic spectroscopy and an optimization algorithm. Finally, I will highlight the impact of spin-orbit couplings and macroscopic and field propagation effects on the phase measurements and APT phase retrieval. Our theoretical description is based on numerical solution of the scalar Maxwell equations beyond Beer’s Law for the macroscopic field propagation coupled to the time-dependent Schroedinger equation for the quantum dynamics.
[1] M. Holler et al., Phys. Rev. Lett. 106, 123601 (2011)
[2] G. R. Harrison et al., arXiv:2305.17263 (2023)
Circuit complexity and functionality: a thermodynamic perspective
We explore a link between complexity and physics for circuits of given functionality. Taking advantage of the connection between circuit counting problems and the derivation of ensembles in statistical mechanics, we tie the entropy of circuits of a given functionality and fixed number of gates to circuit complexity. We use thermodynamic relations to connect the quantity analogous to the equilibrium temperature to the exponent describing the exponential growth of the number of distinct functionalities as a function of complexity. This connection is intimately related to the finite compressibility of typical circuits. Finally, we use the thermodynamic approach to formulate a framework for the obfuscation of programs of arbitrary length – an important problem in cryptography – as thermalization through recursive mixing of neighboring sections of a circuit, which can viewed as the mixing of two containers with “gases of gates”. This recursive process equilibrates the average complexity and leads to the saturation of the circuit entropy, while preserving functionality of the overall circuit. The thermodynamic arguments hinge on ergodicity in the space of circuits which we conjecture is limited to disconnected ergodic sectors due to fragmentation. The notion of fragmentation has important implications for the problem of circuit obfuscation as it implies that there are circuits with same size and functionality that cannot be connected via local moves. Furthermore, we argue that fragmentation is unavoidable unless the complexity classes NP and coNP coincide.
Tunable moire sublattices in twisted square homobilayers: exploiting fundamental principles for new technologies
Stacking and twisting atomically thin bilayers at small angles produces an approximate periodic pattern, due to the overlap of the crystal layers. These devices, dubbed “moire” bilayers, exhibit a high degree of tunability and variability: through choice of twist angle, constituent layers, and gating. To date, a number of such devices have been built which have demonstrated a plethora of novel phases, including non-trivial topology and Mott physics. Despite this explosion in moire research, moire bilayers have been almost exclusively formed from layers with triangular/hexagonal crystal geometry, and where the valence bands are centered on the Gamma or K/K’ high symmetry points. Here we theoretically demonstrate that moire devices formed from square bilayers can be used to simulate the ground state of the Hubbard model, but where the ratio of the nearest-neighbor (t) and next-to-nearest neighbor (t’) tunneling can be tuned between zero and infinity, in situ via an electric field. If experimentally realized, such a device would be the first of its kind, and would open a pathway toward the testing of a number of proposed exotic phases, such as a spin-liquid and d+id superconductivity. Most importantly, the square Hubbard model is a quintessential model for high-Tc in cuprates, where numerics has demonstrated the absence of superconductivity when t’=0.
Graduate student Geoff Harrison, Department of Physics, University of Connecticut
ITAS: A Technique for Complete Quantum Measurements on a New Timescale
Transient absorption spectroscopy is a well-established technique used to study electron dynamics in atomic and molecular systems but typically can only measure the magnitude of the electronic wavefunction. We have integrated interferometric methods into this technique to allow complete quantum measurements of both the magnitude and phase of electronic wavefunctions. A spatial light modulator (SLM) is used to separate the interferometric arms in an extremely stable way, enabling the measurement of effects on the zeptosecond timescale (with a jitter of 3zs). In this talk, I’ll describe how we’ve utilized SLMs to make these measurements possible and share some initial data we’ve taken looking at phase effects in argon.
Dr. Fatma Aslan, Jefferson National Laboratory and UConn
Hadron structure-oriented approach to TMD phenomenology
We present a first practical implementation of a recently proposed hadron structure oriented (HSO) approach to TMD phenomenology applied to Drell-Yan like processes. We compare and contrast general features of our methodology with other common practices and emphasize the improvements derived from our approach that we view as essential for applications where extracting details of nonperturbative transverse hadron structure is a major goal. These include the HSO’s preservation of a basic TMD parton-model-like framework even while accounting for full TMD factorization and evolution, explicit preservation of the integral relationship between TMD and collinear PDFs, and the ability to meaningfully compare different theoretical models of nonperturbative TMD parton distributions.
The Superconducting Diode Effect And Spontaneous Symmetry Breaking In Multi-Layer Graphene
The superconducting diode effect, defined as nonreciprocity in the critical supercurrent, provides a unique window into the nature of the superconducting phase. It has been argued that a zero-field diode effect in the superconducting transport requires inversion and time-reversal symmetries to be simultaneously broken. Along this vein, the zero-field superconducting diode effect in multi-layer graphene provides direct evidence of the microscopic coexistence between superconductivity and time-reversal symmetry breaking. In this talk, I will discuss our recent efforts that utilize the angle-resolved measurement of transport nonreciprocity to directly probe the nature of spontaneous symmetry breaking in the normal phase. By investigating the interplay between transport nonreciprocity, ferromagnetism, and superconductivity, our findings suggest that the exchange-driven instability in the momentum space plays a key role in the zero-field superconducting diode effect.
Graduate student Debadarshini Mishra, Department of Physics, University of Connecticut
Imaging ultrafast dynamics in molecular systems
Imaging electronic and molecular dynamics at the attosecond and femtosecond timescales is crucial for understanding the mechanisms of chemical reactions, a fundamental aspect in fields ranging from materials science to biochemistry. This in-depth understanding of chemical processes may allow for precise control over reaction dynamics, thereby paving the way for advancements in technology and medicine, for example, by guiding the development of efficient catalysis, innovative materials, and targeted drugs. In this talk, I will describe our work on imaging time-resolved molecular dynamics using two distinct and complementary techniques.
In the first part of my talk, I will discuss the use of coincident Coulomb explosion imaging for the direct visualization of roaming reactions. These reactions represent unconventional pathways that allow fragments to remain weakly bonded, leading to the formation of unexpected final products. Typically, the neutral character of the roaming fragment and its indeterminate trajectory make direct experimental identification challenging. However, I will demonstrate that by leveraging the power of coincidence imaging, we can reconstruct the momentum vector of the neutral roamer and thus identify an unambiguous signature for roaming.
In the second part of my talk, I will discuss the imaging of UV-induced ring-opening and dissociation dynamics using ultrafast electron diffraction. I will demonstrate that by harnessing the superior temporal and structural resolution of this technique, we can explore the competition among different molecular pathways as well as their wavelength-dependent behavior.
Novel Strongly Correlated Phases in Stacked TMD Bilayers
Two-dimensional transition metal dichalcogenides (TMDs) have emerged as an exciting platform to stack and twist bilayers to engineer strongly correlated quantum phases. Here we present a theory to describe the recent realization of a heavy fermion state in stacked MoTe2/WSe2 bilayers. An extension of this theory that allows for the formation of unconventional superconductivity through repulsive nearest neighbor interactions will be used to show how to realize the p-wave BEC to BCS transition.
Dr. François Légaré, Institut national de la recherche scientifique, Energy Materials Télécommunications center
Ultrafast IR/mid-IR laser technologies and their applications at ALLS
The Advanced Laser Light Source (ALLS) is a unique user facility located at INRS-EMT (Varennes, Canada) counting on 40M CDN$ of investment since 2002. Since 2019, this facility has jointed the LaserNetUS network and is now funded as a national research infrastructure by the Canada Foundation for Innovation – Major Science Initiatives. These fundings ease access to the facility for academic and government users. In the first part of my talk, I will give an overview of the facility’s capabilities including the most powerful laser in Canada with 750 TW. In the second part, I will discuss novel approaches developed by my team for the generation of ultrashort pulses in the IR and mid-IR spectral range. This includes multidimensional solitary states in hollow core fibers [1,2] as well as using the frequency domain optical parametric amplification for the generation of tunable CEP stable mid-IR laser pulses [3,4]. Pulse characterization in the mid-IR spectral range will be presented [5]. Finally, I will present recent results on the generation of high-dose MeV electrons from tight focussing in air [6].
References
[1] R. Safaei, G. Fan, O. Kwon, K. Légaré, P. Lassonde, B. E. Schmidt, H. Ibrahim, and F. Légaré (2020), High-energy multidimensional solitary states in hollow core fiber, Nature Phot. 14, 733-739.
[2] L. Arias, A. Longa, G. Jargot, A. Pomerleau, P. Lassonde, G. Fan, R. Safaei, P. Corkum, F. Boschini, H. Ibrahim, and F. Légaré, Few-cycle Yb laser source at 20 kHz using multidimensional solitary states in hollow-core fibers, Opt. Lett. 47, 3612-3615 (2022).
[3] A. Leblanc, G. Dalla-Barba, P. Lassonde, A. Laramée, B. Schmidt, E. Cormier, H. Ibrahim, and F. Légaré (2020), High-field mid-infrared pulses derived from frequency domain optical parametric amplification, Opt. Lett. 45, 2267-2270.
[4] G. Dalla-Barba, G. Jargot, P. Lassonde, S. Tóth, E. Haddad, F. Boschini, J. Delagnes, A. Leblanc, H. Ibrahim, E. Cormier, and F. Légaré, Mid-infrared frequency domain optical parametric amplifier, Opt. Express 31, 14954-14964 (2023).
[5] A. Leblanc, P. Lassonde, S. Petit, J.-C. Delagnes, E. Haddad, G. Ernotte, M. R. Bionta, V. Gruson, B. E. Schmidt, H. Ibrahim, E. Cormier, and F. Légaré (2019), Phase-matching-free pulse retrieval based on transient absorption in solids, Opt. Express 27, 28998.
[6] S. Vallières, J. Powell, T. Connell, M. Evans, M. Lytova, F. Fillion-Gourdeau, S. Fourmaux, S. Payeur, P. Lassonde, S. MacLean, and F. Légaré, High Dose-Rate MeV Electron Beam from a Tightly-Focused Femtosecond IR Laser in Ambient Air (2024), Laser Photonics Rev. 18, 2300078.
François Légaré is a chemical physicist who specializes in developing novel approaches for ultrafast science and technologies, as well as biomedical imaging with nonlinear optics (Ph.D. in chemistry, 2004 – co-supervised by Profs. André D. Bandrauk and Paul B. Corkum). Full professor (2013 - …) at the Energy Materials Telecommunications center of the Institut national de la recherche scientifique (INRS-EMT), he was the director of the Advanced Laser Light Source (ALLS) until 2023. Since 2022, he is the director of the INRS-EMT center and CEO of ALLS. Under his scientific leadership, INRS has received in 2017 a grant of 13.9M CDN$ from the Canada Foundation for Innovation and the Quebec government, with 11.9M CDN$ to upscale the ALLS facility with high average power Ytterbium laser systems and advanced instrumentation for time-resolved material characterization. He is a Fellow and senior member of OPTICA and Fellow of the American Physical Society. He is a member of The College of New Scholars, Artists and Scientists of the Royal Society of Canada (2017). He was awarded the Herzberg medal from the Canadian Association of Physics in 2015 and the Rutherford Memorial Medal in physics of the Royal Society of Canada in 2016. He has contributed to about 200 articles in peer reviewed journals including prestigious ones such as Nature, Science, Nature Photonics, Nature Physics, Nature Communications, and Physical Review Letters. According to Google Scholar, his h-index is 59 with more than 13,000 citations.
I will discuss experiments and calculations that demonstrate long lived electronic coherences in molecules using a combination of measurements with shaped octave spanning ultrafast laser pulses, 3D velocity map imaging and calculations of the light matter interaction. Our pump-probe measurements prepare and interrogate entangled nuclear-electronic wave packets whose electronic phase remains well defined despite vibrational motion along many degrees of freedom. The experiments and calculations illustrate how coherences between excited electronic states survive even when coherence with the ground state is lost, and may have important implications for light harvesting, electronic transport and attosecond science.
Fully Consistent NLO Calculation of Forward Single-Inclusive Hadron Production in Proton-Nucleus Collisions
We study the single-inclusive particle production from proton-nucleus collisions in the dilute-dense framework of the color glass condensate (CGC) at next-to-leading order (NLO) accuracy. In this regime, the cross section factorizes into hard impact factors and dipole-target scattering amplitude describing the eikonal interaction of the partons in the target color field. For the first time, we combine the NLO impact factors with the dipole amplitude evolved consistently using the NLO Balitsky-Kovchegov (BK) equation with the initial conditions fitted to HERA structure function data.
The resulting neutral pion cross section with all parton channels included are qualitatively consistent with the recent LHCb measurement. In particular, the NLO evolution coupled to the leading order impact factor is shown to produce a large Cronin peak that is not visible in the data, demonstrating the importance of consistently including NLO corrections to all the ingredients. Furthermore, the transverse momentum spectrum is found to be sensitive to the resummation scheme and the running coupling prescription in the BK evolution. This demonstrates how additional constraints for the initial condition of the BK evolution can be obtained from global analyses including both the HERA and LHC data. In light of the upcoming upgrades to the LHC, the dependence of our results on rapidity will also be discussed.
Scattering amplitudes are the arena where quantum field theory meets particle experiments, for example at the Large Hadron Collider where the copious scattering of quarks and gluons in quantum chromodynamics (QCD) produces Higgs bosons and many backgrounds to searches for new physics. Particle scattering in QCD and other gauge theories is far simpler than standard perturbative approaches would suggest. Modern approaches based on unitarity and bootstrapping dramatically simplify many computations previously done with Feynman diagrams. Even so, the final results are often highly intricate, multivariate mathematical functions, which are difficult to describe, let alone compute. In many cases, the functions have a “genetic code” underlying them, called the symbol, which reveals much of their structure. The symbol is a linear combination of words, sequences of letters analogous to sequences of DNA base pairs. Understanding the alphabet, and then reading the code, exposes the physics and mathematics underlying the scattering process, including new symmetries. For example, the two scattering amplitudes that are known to the highest orders in perturbation theory (8 loops) are related to each other by a mysterious antipodal duality, which involves reading the code backwards as well as forwards. A third scattering amplitude, which contains both of these as limits, has an antipodal self-duality which “explains” the other duality. However, we still don’t know `who ordered’ antipodal (self-)duality, or what it really means.
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