Daniel McCarron wins NSF Early Career Award
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.
[Read More]
Meet the Researcher: Carlos Trallero
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.
[Read More]
2019 Pollack Lecture
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 […]
[Read More]
2 for the price of 1: UConn researcher finds new mechanism making double ionization an efficient process
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 […]
[Read More]
Nora Berrah Named 2018 AAAS Fellow
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.
[Read More]
Prof. C. Trallero awarded multiple research grants
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.
[Read More]
Ultracold group achieves new milestone in quantum control
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 […]
[Read More]
Undergraduate Sam Entner traps cold atoms in Physics lab for summer research project
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 […]
[Read More]-
Dr. Antonio Picón, Departamento de Química, Facultad de Ciencias, Universidad Autónoma de Madrid, "Mapping the real-time movies of chemical bonds", Atomic, Molecular, And Optical Physics Seminar4:00pm
3/3
Dr. Antonio Picón, Departamento de Química, Facultad de Ciencias, Universidad Autónoma de Madrid, "Mapping the real-time movies of chemical bonds", Atomic, Molecular, And Optical Physics Seminar
Wednesday, March 3rd, 2021
04:00 PM - 05:00 PM
Storrs Campus online
Dr. Antonio Picón, Departamento de Química, Facultad de Ciencias, Universidad Autónoma de Madrid
Mapping the real-time movies of chemical bonds
Valence electrons play a crucial role in the formation of chemical bonds within a molecular system and determine its charge and electron transfer properties. In the static regime, these properties are defined by the electron density distribution of the equilibrium geometry. However, when out of equilibrium, ultrafast electronic rearrangements within the order of a few femtoseconds together a significant alteration of the chemical bonds can occur. I will address in this talk our undergoing investigations for mapping these ultrafast changes through X-ray photoelectron spectroscopy that have been critical in retransforming the well-established concepts of chemical shifts. I will additionally illustrate our developments for the selective manipulation of chemical bonding through X-ray free electron laser pulses. -
Dr. H. Larsson, California Institute of Technology, "Molecules in quantum motion --- Understanding electrons, nuclei, and their interactions", Atomic, Molecular, And Optical Physics Seminar4:00pm
3/1
Dr. H. Larsson, California Institute of Technology, "Molecules in quantum motion --- Understanding electrons, nuclei, and their interactions", Atomic, Molecular, And Optical Physics Seminar
Monday, March 1st, 2021
04:00 PM - 05:00 PM
Storrs Campus online
Dr. H. Larsson, California Institute of Technology
Molecules in quantum motion ---
Understanding electrons, nuclei, and their interactions
In order to fully understand the chemical physics of molecular systems, we need to simulate both the electronic and vibrational motion quantum mechanically. However, simulations of quantum many-body systems, such as molecules, scale exponentially with system size. I will explain how to tame this 'curse of dimensionality' by combining methods from the traditionally disjoint fields of electronic structure and nuclear dynamics. This combination has enabled the simulation of complex systems with unprecedented accuracy and speed. I will demonstrate how these methods make it possible to solve a diverse set of problems, ranging from characterizing hydrated protons on a molecular quantum level to the interaction of molecules with extremely short and intense light pulses on attosecond time scales. I will demonstrate how these simulations provide new insight into complex fundamental physical processes. -
Dr. Jean Marcel Ngoko Djiokap, Department of Physics & Astronomy, University of Nebraska, Lincoln, "Control of Electron Motion on an Attosecond Timescale ", Atomic, Molecular, And Optical Physics Seminar4:00pm
2/24
Dr. Jean Marcel Ngoko Djiokap, Department of Physics & Astronomy, University of Nebraska, Lincoln, "Control of Electron Motion on an Attosecond Timescale ", Atomic, Molecular, And Optical Physics Seminar
Wednesday, February 24th, 2021
04:00 PM - 05:00 PM
Storrs Campus online
Dr. Jean Marcel Ngoko Djiokap, Department of Physics & Astronomy, University of Nebraska, Lincoln
Control of Electron Motion on an Attosecond Timescale
Technological advances 20 years ago in producing new extreme ultraviolet coherent light sources with attosecond duration have created a new research field, namely, attosecond physics. A main goal of attosecond physics is to control electron motion on its natural (attosecond) timescale, in order to probe bond formation and breaking in molecules during chemical reactions. A milestone toward achieving such goal is the experimental realization of isolated, few-cycle, attosecond pulses seeded by a free electron laser (FEL) or high harmonic generation (HHG) with stable and tunable carrier-envelope phase (CEP), and with full control of their polarizations. Unlike HHG, X-ray attosecond pulses from FEL have sufficient intensities that permit the realization of the holy grail (atto-pump/atto-probe experiments) of attosecond physics. Use of circularly or elliptically polarized attosecond light opens the possibility of presently investigating and manipulating linear and nonlinear effects that are not accessible with linearly-polarized pulses. In this talk, after briefly introducing the physical mechanisms at the basis of attosecond pulse generation, I will focus on our numerical and analytical methods for the investigation of ultrafast ionization processes in atoms and molecules of astrophysical interest, with emphasis on two-electron processes in which electron correlations play a key role. Enabled by the broad bandwidth of attosecond pulses, the first unusual effect we predicted in double photoionization of H2 by an intense few-cycle elliptically polarized attosecond pulse is the molecular symmetry-mixed dichroism (MSMD. The other effect is the novel electron phenomenon of electron vortices in attosecond photoionization of atoms and molecules, which provides a dramatic example of wave-particle duality. Our predictions of electron matter-wave vortices, which have now been observed experimentally, have already opened a new interdisciplinary area in physics. -
Dr. Anh-Thu Le, Missouri University of Science and Technology, "Toward Ultrafast Molecular Imaging with Intense Laser Pulses ", Atomic, Molecular, And Optical Physics Seminar4:00pm
2/17
Dr. Anh-Thu Le, Missouri University of Science and Technology, "Toward Ultrafast Molecular Imaging with Intense Laser Pulses ", Atomic, Molecular, And Optical Physics Seminar
Wednesday, February 17th, 2021
04:00 PM - 05:00 PM
Storrs Campus online
Dr. Anh-Thu Le, Missouri University of Science and Technology
Toward Ultrafast Molecular Imaging with Intense Laser Pulses
High harmonic generation (HHG), laser-induced electron diffraction, and other rescattering phenomena are at the heart of strong-field and attosecond physics. However, it is challenging to interpret experimental measurements as accurate ab initio calculations for molecules in intense laser fields are essentially prohibitive. Recently, we developed the quantitative rescattering theory to provide a simple solution to this problem. Our theory establishes direct links between these strongly nonlinear processes with the well-studied traditional scattering processes, thereby making realistic simulations possible. More importantly, our theory allows straightforward decoding of the imprints of the target structure from the experimental data. In this talk, I will present our recent contributions in interpreting different experiments and reconstructing molecular structure for targets that undergo ultrafast transformations. Furthermore, I will also discuss our progress in molecular imaging with ultrafast soft X-ray pulses from HHG or free-electron laser sources. Finally, I will discuss the challenges and our future directions in developing theoretical tools for practical realization of molecular "movies" with atomic resolution in space and time that can provide new insights into fundamental chemical reactions. -
Dr. Francois Mauger, Department of Physics & Astronomy, Louisiana State University, " Watching electrons move in molecules", Atomic, Molecular, And Optical Physics Seminar4:00pm
2/15
Dr. Francois Mauger, Department of Physics & Astronomy, Louisiana State University, " Watching electrons move in molecules", Atomic, Molecular, And Optical Physics Seminar
Monday, February 15th, 2021
04:00 PM - 05:00 PM
Storrs Campus online
Dr. Francois Mauger, Department of Physics & Astronomy,
Louisiana State University
Watching electrons move in molecules
Electrons are the glue that holds matter together: Their spatial arrangement defines chemical bonds, and their time evolution controls reactions. But electrons are light, and they move fast, reaching down to the femtosecond and attosecond regimes. So probing dynamics at the spatial and temporal scales of electron motions in molecules is a formidable challenge, one that holds the promise of going beyond the "what happened" of spectroscopy to the "how did that happen" that a movie provides. New ultrafast light sources, like X-ray lasers and table-top attosecond sources, together with state-of-the-art theoretical tools are opening this frontier. In this talk I will discuss recent developments and future perspectives for watching coherent electron motion in molecules. This research, at the frontier of ultrafast science, involves cross-disciplinary approaches intersecting atomic and molecular physics and chemistry, optics and lasers, applied mathematics and computer science.