Research, teaching and outreach in Physics at UW–Madison
Awards and Honors
Ben Woods and team named finalists in 2023 WARF Innovation Awards
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Each fall the WARF Innovation Awards recognize some of the best inventions at UW–Madison. WARF receives hundreds of new invention disclosures each year. Of these disclosures, the WARF Innovation Award finalists are considered exceptional in the following criteria:
Has potential for high long-term impact
Presents an exciting solution to a known important problem
Could produce broad benefits for humankind
One of the six finalists comes from Physics. Research Associate Benjamin Woods and a team including Distinguished Scientist Mark Friesen, John Bardeen Prof. of Physics Mark Eriksson, Honorary Associate Robert Joynt, and Graduate Student Emily Joseph developed a quantum device that shows a significant increase in valley splitting, a key property needed for error-free quantum computing. The device features a novel structural composition that turns conventional wisdom on its head.
Two winners, selected from the six finalists, will be announced in WARF’s annual holiday greeting; sign up to receive the greeting here. Each of the two Innovation Award winners receive $10,000, split among UW inventors.
Victor Brar earns NSF CAREER award
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Congrats to associate professor Victor Brar on earning an NSF CAREER award! CAREER awards are NSF’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 mission of their department or organization.
Victor Brar
For this award, Brar will study the flow of electrons in 2D materials, or materials that are only around one atom thick. His group has already shown that when they applied a relatively old technique — scanning tunneling potentiometry, or STP — to 2D materials such as graphene, they could create unexpectedly high-contrast images, where they could track the movement of individual electrons when an electric current was applied. They found that electrons flow like a viscous fluid, a property that had been predicted but not observed directly.
“So now instead of applying electrical bias, we’ll apply a thermal bias, because we know things move from hot to cold, and then image how [electrons] move in that way,” Brar says. “Part of what’s driving this idea is that Professor Levchenko has predicted that if you image the way heat flows through a material, it should also behave hydrodynamically, like a liquid, rather than diffusive, which is how you might imagine it.”
One motivation for this research is to better understand the general flow of fluids, a problem that is often too complex for supercomputers to solve correctly. Because STP visualizes the fluid-like flow of electrons directly, Brar envisions this work as potentially providing a way of solving fluid mechanics problems by directly imaging flow, without the need of simulations, similar to what is done in wind tunnels.
“Also, there are these predicted phases of electrons that no one has observed before,” Brar says. “We want to be the first to observe them.”
In addition to an innovative research component, NSF proposals require that the research has broader societal impacts, such as working toward greater inclusion in STEM or increasing public understanding of science. Brar’s group is using haptic pens, devices that are commonly used in remote trainings for surgeons and in the gaming community because they give a gentle push back that mimics a realistic touch. By attaching the haptic pen to a scanning tunneling microscope (STM), people holding the pen can “feel” the individual atoms and surfaces that the STM is touching.
“We think materials science is one of those areas where feeling the forces that hold matter together may provide more intuitive than looking at equations,” Brar says. “We’re making virtual crystal lattices that you can touch with the haptic pen and feel how the atoms fix together, but we’re also making it so you can feel the different forces of the different atoms used.”
Brar plans to introduce the haptic pen and atom models into Physics 407 and develop a materials science module for the UW Alumni Association’s Grandparents University. And because the haptic pen relies almost entirely on touch, Brar plans to work with the Wisconsin Council of the Blind and Visually Impaired to improve access to materials science instruction for people with vision impairments.
Physics has three winners in the Cool Science Image contest!
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The winners of the UW–Madison 13th annual Cool Science Image contest were announced, and Physics has three winners! Our winners include graduate student Jacob Scott, the graduate student-professor pairing of Jimena González and Keith Bechtol, and alum Aedan Gardill, PhD ’23. Their winning images are below.
A panel of experienced artists, scientists and science communicators chose 12 winning images based on the aesthetic, creative and scientific qualities that distinguished them from scores of entries. The winning entries showcase the research, innovation, scholarship and curiosity of the UW–Madison community through visual representations of socioeconomic strata, brain cells snuffed out in Parkinson’s disease, the tangle of technology required to equip a quantum computing lab and a bug-eyed frog that opened students’ eyes to the world.
The winning images go on display this week in an exhibit at the McPherson Eye Research Institute’s Mandelbaum and Albert Family Vision Gallery on the ninth floor of the Wisconsin Institutes for Medical Research, 111 Highland Ave. The exhibit, which runs through the end of 2023, opens with a public reception at the gallery Thursday, Sept. 28, from 4:30 to 6:30 p.m. The exhibit also includes historical images of UW science, in celebration of the 175th anniversary of the University of Wisconsin’s founding.
The Cool Science Image Contest recognizes the technical and creative skills required to capture and create images, videos and other media that reveal something about science or nature while also leaving an impression with their beauty or ability to induce wonder. The contest is sponsored by Madison’s Promega Corp., with additional support from UW–Madison’s Office of University Communications.
The glow of red and green lasers and an array of supporting electronics fill a UW–Madison lab where physicists study the behavior of cesium atoms cooled within a fraction of a degree of absolute zero. The atoms could be used to store information in quantum computing systems. | Jacob ScottLike the radiation she studied, this portrait of physicist Marie Curie is invisible until revealed by the proper equipment — in this case, a polarizer, a filter that blocks all light waves except those oscillating in a certain direction. One polarizing filter on the back layer of the portrait organizes the light shining through to the viewer. That light passes through layers of colorless cellophane, which rotate the waves a little or a lot depending on the layer’s thickness. A second polarizing filter, held by the viewer, filters the light again, selecting light at the wavelengths that correspond to the intended colors of the portrait. The image above is as the portrait appears viewed through a polarizer. | Aedan Gardill PhD ’23Each image in this collage is of an astronomical phenomenon known as a strong gravitational lens, in which the light from a galaxy or cluster of galaxies is curved by a massive object in the foreground. The light is distorted into bright arcs, exhibiting physics theorized by Albert Einstein. Strong gravitational lenses offer a way to study dark matter, difficult to detect but considered a crucial factor in the structure, evolution and fate of the cosmos. | Jimena González and Keith Bechtol
Jimena González wins 2023 OSG David Swanson Award
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Early in her thesis research, Jimena González was waiting. A lot.
To better understand the nature of dark energy, she uses machine learning to search Dark Energy Survey cosmology data for evidence of strong gravitational lensing — where a heavy foreground galaxy bends the light of another galaxy, producing multiple images of it that can get so distorted that they appear as long arcs of light around the large galaxy in telescope images. She also focuses on finding very rare cases of strong gravitational lensing in which two galaxies are lensed by the same foreground galaxy, systems known as double-source-plane lenses.
First, she had to create simulations of the galaxy systems. Next, she used those simulations to train the machine learning model to identify the systems in the heaps and heaps of DES data. Lastly, she would apply the trained model to the real DES data. All told, she expected to find hundreds of “simple” strong gravitational lenses and only a few double-source-plane lenses out of 230 million images.
“But, for example, when I did the search the first time, I mostly only got spiral galaxies, so then I had to include spiral galaxies in my training,” says González, a physics graduate student in Keith Bechtol’s group.
The initial steps took around two weeks (hence the waiting) before she could even know what needed to be changed to better train the model. Once she had the model trained and would be ready to apply it to the entire dataset, she estimated it would take five to six years just to find the images of interest — and then she would finally be able to study the systems found.
Jimena González presents an award lecture at the 2023 Throughput Computing Conference. (provided by Jimena González)
Then, the email from the Open Science Grid (OSG) Consortium came. The OSG Consortium operates a fabric of distributed High Throughput Computing (dHTC) services, allowing users to take advantage of massive amounts of computing power. Researchers can apply to the OSG User School, an annual workshop for scientists who want to learn and use dHTC methods.
“[dHTC] is parallelizing things. It’s like if you had 500 exams to grade, you can distribute them among different people and it would take less time,” González says. “It sounded perfect for me.”
González applied and was accepted into the 2021 program, which was run virtually that year. At the OSG User School, she learned methods that would allow her to take advantage of dHTC and apply them to her work. Her multi-year processing time was cut down to mere days.
“Because it was so fast, there were many new things that I could implement in my research,” González says. “A lot of the methodology I implemented would not have been possible without OSG.”
David Swanson was a longtime champion of and contributor to OSG, who passed away in 2016. In his memory, the award is bestowed annually upon one or more former students of the OSG User School who have subsequently achieved significant dHTC-enabled research outcomes.
She accepted the award at the Throughput Computing 2023 conference, where she presented her research and discussed how she used her training from the OSG User School to successfully comb through the DES data and find the systems of interest.
“When I got the award, I didn’t know anything about [Swanson],” González says. “But once I attended this event, I heard so many people talking about him, and I understood why it was created. It is such an honor to receive this award in his name.”
Choy leads team awarded National Science Foundation Quantum Sensing Challenge Grant
The National Science Foundation has selected a proposal “Compact and robust quantum atomic sensors for timekeeping and inertial sensing” by an interdisciplinary team led by University of Wisconsin-Madison researchers for...
IceCube collaborator and UW–Madison assistant professor of physics Lu Lu received a 2023 International Union of Pure and Applied Physics (IUPAP) Early Career Scientist Prize “for her contributions to the development of high energy neutrino astronomy in the PeV energy region.” Lu accepted the award on July 27 during the opening ceremony at the 38th International Cosmic Ray Conference (ICRC) held in Nagoya, Japan.
Lu Lu
Early Career Scientist Prizes are given to early career scientists within each IUPAP commission who have up to eight years of postdoctoral research experience and have made significant contributions to the cosmic ray field. Lu is a recipient of the Early Career Scientist Prize in the Commission on Astroparticle Physics (C4).
Her PhD work focused on developing a novel technique to search for ultra-high-energy photons using data from the Pierre Auger Observatory. She also played a leading role in the initial design of the “Dual optical sensors in an Ellipsoid Glass for Gen2” (D-Egg), a two-PMT optical module for the IceCube Upgrade.
Lu is currently an assistant professor of physics at the Wisconsin IceCube Particle Astrophysics Center (WIPAC) at the University of Wisconsin–Madison. Her current research focuses on diffuse high-energy astrophysical/cosmogenic neutrinos from TeV to EeV, Galactic PeVatron detection in the context of multimessenger observations, and the exploration of potential transient ultra-high-energy sources.
She is actively involved in IceCube outreach initiatives and has pioneered the development of an app that provides IceCube real-time alerts via augmented reality on mobile devices. Currently, she serves as co-lead of the diffuse science working group in IceCube and is one of three representatives of the physical science group of US-SCAR (Scientific Committee of Antarctic Research).
“I would like to express my deep appreciation for my collaborators and for those who work on foundational tasks such as reconstructions and calibrations, as their efforts behind the scenes make groundbreaking discoveries possible,” said Lu. “As early career scientists, we bear the responsibility of continuing and expanding experiments in the particle astrophysics field. We must collaborate and work together to ensure that the next generation of young scientists will have exciting discoveries to make.”
Keith Bechtol, Victor Brar promoted to Associate Professors
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Congratulations to Keith Bechtol and Victor Brar, who were both promoted to associate professors of physics with tenure!
Keith Bechtol
Bechtol is an observational cosmologist with research interests in dark matter and dark energy, using the whole Universe as a lab to understand the fundamental physics of nature. He is part of the Dark Energy Survey (DES) that has cataloged more 500 million galaxies and thousands of supernovae to understand the nature of dark energy. He and his group are also working on the construction and commissioning of the Vera C. Rubin Observatory in preparation for the Legacy Survey of Space and Time (LSST). LSST is expected to catalog more stars, more galaxies and more solar system objects during its first year of operations than all previous telescopes combined.
“Professor Bechtol plays a leading role in the Vera C. Rubin Observatory, which is now poised to enable a major leap in the data available for understanding the development of our universe,” says Mark Eriksson, Chair and John Bardeen Professor of Physics.
Bechtol was a co-convener of the DES’s Science Release Working Group for four years and a co-convener of the Milky Way Working Group for two years. He is now serving as Technical Coordinator for the LSST Dark Energy Science Collaboration. In 2022, he was selected to the Department of Energy’s Early Career Research Program. He also proposed and is the faculty lead for the physics department’s Thaxton Fellowship, whose goal is to provide more equitable access to physics research experiences for undergraduates.
Victor Brar
Brar, the Van Vleck professor of physics and a member of the Wisconsin Quantum Institute, is an experimental condensed matter physicist with a research focus on quantum materials and novel imaging techniques. His group works on developing metamaterials such as 2D materials for use in laser sailing or fabricating graphene structures for use in telecommunications. They also use scanning tunneling microscopy and scanning tunneling potentiometry to understand the physical and electrical properties of materials.
“The experiments performed by Professor Brar and his research team have enabled measurements of completely new regimes for electron transport in 2D materials,” Eriksson says.
Brar was awarded a Moore Inventor Fellowship in 2018, a Sloan Fellowship in 2021, and a National Science Foundation CAREER award in 2023. He has additionally received two UW–Madison Research Forward awards.
Undergraduates named 2023 Hilldale Fellows
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Physics major Dhanvi Hiriyanna Bharadwaj has been named a 2023 Hilldale Fellow, working with Ramathasan Thevamaran in Mechanical Engineering. Astronomy-physics major Vicki Braianova, who is working with physics professor Peter Timbie, has also received the award.
The Hilldale Undergraduate/Faculty Research Fellowship provides research training and support to undergraduates at UW–Madison. Students have the opportunity to undertake their own research project in collaboration with UW–Madison faculty or research/instructional academic staff. Approximately 97 – 100 Hilldale awards are available each year.
Alex Levchenko honored with H.I. Romnes Fellowship
Physics professor Alex Levchenko was one of thirty-five of the University of Wisconsin–Madison faculty to be awarded fellowships from the Office of the Vice Chancellor for Research and Graduate Education for 2023-24. The awardees span the four divisions on campus: arts and humanities, physical sciences, social sciences and biological sciences.
“These awards recognize our faculty research, academic and outreach successes and provide an opportunity for continued development of their outstanding research programs,” says Steve Ackerman, vice chancellor for research and graduate education. “I’m grateful that we are able to recognize invest in these faculty in this way, and I look forward to seeing the results of their imaginative use of these funds.”
The awards are possible due to the research efforts of UW–Madison faculty and staff. Technology that arises from these efforts is licensed by the Wisconsin Alumni Research Foundation and the income from successful licenses is returned to the OVCRGE, where it’s used to fund research activities and awards throughout the divisions on campus.
Eighteen faculty, including Levchenko, have been honored with the H.I. Romnes Fellowships to recognize faculty with exceptional research contributions within their first six years from promotion to a tenured position. The award is named in recognition of the late WARF trustees president H.I. Romnes and comes with $60,000 that may be spent over five years.
Levchenko studies fundamental aspects of condensed matter physics with a focus on electronic phases of matter and quantum transport. Specific areas of expertise include superconductivity, topological order, and nanoscale systems such as graphene and other van der Waals materials. He is a Fellow of the American Physical Society and of the Alexander von Humboldt Foundation, and recipient of an early career grants from the National Science Foundation and the Binational Science Foundation. His teaching covers all levels of undergraduate and graduate education, and he serves on multiple professional review panels internationally.
Victor Brar, Wisconsin Center for Semiconductor Thermal Photonics earn UW Research Forward funding
The Wisconsin Center for Semiconductor Thermal Photonics will explore fundamental science at the intersection of semiconductor technology and radiative heat transfer. This cross-disciplinary center will explore thermal radiation in unconventional semiconductor materials, in nanostructures, and in extreme conditions, and achieve control of the directionality and timing of radiative heat transfer at unprecedented scales. New technologies will emerge from these fundamental studies, including low-cost spectrometers, imaging and ranging, and energy harvesting and active cooling.
The project is led by ECE associate professor and physics affiliate professor Mikhail Kats as Principal Investigator, with Physics associate professor Victor Brar as one of the co-PIs.
Research Forward, a competition sponsored by the Office of the Vice Chancellor for Research and Graduate Education (OVCRGE), is intended to stimulate and support highly innovative and groundbreaking research at UW–Madison.
The initiative is supported by the Wisconsin Alumni Research Foundation (WARF) and will provide funding for 1–2 years, depending on the needs and scope of the project.
