Research, teaching and outreach in Physics at UW–Madison
Undergraduate
Physics major Caleb Youngwerth wins poster prize at APS Eastern Great Lakes meeting
Posted on
Caleb Youngwerth
Congrats to physics, astronomy-physics, mathematics and french major Caleb Youngwerth on winning the Meeting Award for Undergraduate Student Poster at the Fall 2024 meeting of the Eastern Great Lakes Section of APS!
Youngwerth’s poster, entitled, “Harnessing Molecular Simulation of the DLVO Potential to Engineer New Battery Technologies,” was presented at the meeting held October 18-19 at Marietta College in Ohio. The work was conducted in the chemical and biological engineering group of Prof. Rose Cersonsky.
The award was announced at the meeting and comes with a cash prize.
Four physics majors have earned 2024 Hilldale Fellowships. They are:
Erica Magee, Mathematics and Physics major, working with Martin Zanni (Chemistry)
Quinn Meece, Astronomy – Physics and Physics major, working with Mark Saffman (Physics)
Elias Mettner, Physics major, working with Abdollah Mohammadi (Physics)
Leah Napiwocki, Astronomy – Physics and Physics major, working with Marsha Wolf (Astronomy)
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.
The student researcher receives a $3,000 stipend (purpose unrestricted) and faculty/staff research advisor receives a $1,000 stipend to help offset research costs (e.g., supplies, books for the research, student travel related to the project).
Two physics students win presentation awards at APS April Meeting
Posted on
Elias Mettner and Nadia Talbi, both conducting research in high energy physics at UW–Madison, won undergraduate presenter awards at the American Physical Society’s April Meeting.
The meeting, held in Sacramento April 3-6, included seven undergraduate oral presentation sessions with six to eight students in each session. The top two students from each session earned “Top Presenter” awards. Mettner and Talbi were the only two UW–Madison students who gave oral presentations, and both won awards.
Elias Mettner
Mettner is a physics major working with scientist Abdollah Mohammadi. His talk was titled “Pair Production and Hadron Photoproduction Backgrounds at the Cool Copper Collider.”
The Cool Copper Collider is a proposed electron-positron collider that will help scientists to explore the Higgs boson even further. The electron-positron beam will have some natural decay that converts into particles and is recorded by the detector. Mettner’s research asks how this beam background will impact the detector.
“The detector will record this background, and it could take the place of the data we want or make it harder to reconstruct data,” Mettner says. “It’s important to make sure that the backgrounds that will come into the detector using this new design will not cause any issues, otherwise the benefits of this collider design cannot be put to their maximum use.”
Mettner had been interested in physics from a young age and comes from a family of teachers who encouraged him to explore his academic interests. Upon entering UW–Madison, he jumped at the chance to conduct research in particle physics. He joined the UW CMS Collaboration in his freshman year through the Undergraduate Research Scholars program and began his project with the Cool Copper Collider soon after. He was also awarded the Sophomore Research Fellowship for his junior year and the Hilldale Research Fellowship for his upcoming senior year.
Nadia Talbi presents at APS April Meeting
Talbi is an astronomy-physics major working in physics professor Tulika Bose’s group and mentored by postdoc Charis Koraka. Her talk, “A Search for Vector-Like Leptons: Compact Analysis,” covered work she has done through a Thaxton Fellowship.
“Bosons are force particles, and basically every boson except for the Higgs — the photon, the gluon — is a vector boson. Leptons are electrons, muons, neutrinos, stuff like that,” Talbi explains. “Vector-like leptons are a hypothetical particle, we don’t know whether or not they exist.”
Talbi was drawn to astronomy because she has long had an interest in the fundamental nature of the universe. As a child, she read an article on Dark Matter and, later, a friend gave her a book on the Standard Model. She was hooked. When she applied for the Thaxton Fellowship, a departmental program that was started to provide more equitable access to undergraduate research in physics, she discussed her interest in particle physics and the research at CERN, which landed her in Bose’s group.
“So before I even had any formal education in physics, where things can be very black and white, I’ve had the opportunity to understand the beautiful things within the field,” Talbi says. “Studying physics, I think, gives you some of the most fundamental understanding of our existence.”
Both Metter and Talbi say that attending conference was overall a very worthwhile experience — even if they both had to take an E+M exam remotely before presenting. (“It was a good bonding experience,” Talbi says.)
“The conference was a lot of fun, and worth it to go and make some connections and experience a bunch of really interesting research from people all in different stages of their careers,” Mettner says.
Adds Talbi: “There were so many undergraduates there, I met so many, I made a lot of friends. It felt like there was a community.”
Both students were also invited to present their award-winning talks to the Physics Board of Visitors spring meeting.
On Saturday, April 13, physics students Will Cerne and William Griffin were among the 168 University of Wisconsin–Madison Letters & Science undergraduates inducted to the Phi Beta Kappa (ΦΒΚ) academic society. The induction ceremony was held at Varsity Hall in Union South with 350 attending.
In addition to the induction of new undergraduate members, the ceremony also honored four individuals for their contributions to UW–Madison, including Jimena González, a member of the UW–Madison chapter of the Edward A. Bouchet Society and a PhD candidate in Physics (observational cosmology). González accepted one of ΦΒΚ’s graduate student induction invitation.
UW–Madison’s ΦΒΚ chapter, founded in 1899, seeks to honor students who rigorously explore the sciences, arts and humanities.
L&S Dean Eric M. Wilcots led the opening procession and welcome. Chapter President David W. Johnson, economics, hosted the celebration’s 125th year of the founding of the UW–Madison chapter of Phi Beta Kappa. Special guest and president of the national Phi Beta Kappa Society Peter Quimby PhD’99 presented the history of ΦΒΚ. ΦΒΚ stands for philosophia biou kubernetes, which translates to “the love of wisdom is the helmsman of life.”
Inductees excel in all areas of study, ranging from physics to anthropology, and they must have a cumulative GPA of 3.80 or above and meet strenuous math, language, and breadth requirements.
A committee of faculty and staff review the student record for nomination into the chapter. Inductees have a love for learning in multiple areas of study at the intermediate and advanced levels, exploring far beyond their major area of study at UW–Madison.
Jim Reardon wins WISCIENCE Lillian Tong Teaching Award
Posted on
Each year, the University of Wisconsin–Madison recognizes outstanding academic staff members who have excelled in leadership, public service, research and teaching. These exceptional individuals bring the university’s mission to life and ensure that the Wisconsin Idea extends far beyond the campus and the state. Ten employees won awards this year, including Dr. Jim Reardon, Director of Undergraduate Program with the department of physics.
Jim Reardon’s love of running and his excellence as a physics instructor recently came together in the classroom in a big way with Physics 106: The Physics of Sports, a course he developed and now teaches. The new course applies physical principles to competitive sports, helping students better understand athletic performance. It’s proven exceptionally popular, attracting almost 140 students in only its third semester.
Jim Reardon, director of undergraduate program in the Department of Physics at the University of Wisconsin–Madison, is pictured while teaching during a Physics 106 class held in Chamberlin Hall on March 20, 2024. Kaul is one of ten recipients of a 2024 Academic Staff Excellence Award (ASEA). (Photo by Bryce Richter / UW–Madison)
Reardon’s expertise at course development, his mastery at instruction and his exemplary support of teaching assistants have made him indispensable to the Physics Department. As director of the undergraduate program, he implemented standardized assessments in the department’s large introductory courses. This provided a baseline for successful course modifications and allowed nationwide peer assessment comparisons. As the administrator of the teaching assistant program, Reardon expertly matches the strengths of TAs with the needs of the department.
Reardon is no less valued in the classroom. Students routinely give him the highest of marks. Writes one, “I have never seen a professor or teacher work so effectively and patiently to ensure his students understood the information.”
♦
“Jim is unique in his broad and ready grasp of the subject matter combined with a passion for teaching and making sure that ALL students have access to that subject matter.”
— Sharon Kahn, graduate program manager, Department of Physics
Bringing the Quantum to the Classical: A Hybrid Simulation of Supernova Neutrinos
Simulating quantum systems on classical computers is currently a near-impossible task, as memory and computation time requirements scale exponentially with the size of the system. Quantum computers promise to solve this scalability issue, but there is just one problem: they can’t reliably do that right now because of exorbitant amounts of noise.
So when UW–Madison physics postdoc Pooja Siwach, former undergrad Katie Harrison BS ‘23, and professor Baha Balantekin wanted to simulate neutrino evolution inside a supernova, they needed to get creative.
Pooja Siwach
Their focus was on a phenomenon called collective neutrino oscillations, which describes a peculiar type of interaction between neutrinos. Neutrinos are unique among elementary particles in that they change type, or flavor, as they propagate through space. These oscillations between flavors are dictated by the density of neutrinos and other matter in the medium, both of which change from the core to the outer layers of a supernova. Physicists are interested in how the flavor composition of neutrinos evolve in time; this is calculated using a time evolution simulation, one of the most popular calculations currently done on quantum computers.
Ideally, researchers could calculate each interaction between every possible pair of neutrinos in the system. However, supernovae produce around 10^58 neutrinos, a literally astronomical number. “It’s really complex, it’s very hard to solve on classical computers,” Siwach says. “That’s why we are interested in quantum computing because quantum computers are a natural way to map such problems.”
Katie Harrison
This naturalness is due to the “two-level” similarities between quantum computers and neutrino flavors. Qubits are composed of two-level states, and neutrino flavor states are approximated as two levels in most physical systems including supernovae.
In a paper published in Physical Review D in October, Siwach, Harrison, and Balantekin studied the collective oscillation problem using a quantum-assisted simulator, or QAS, which combines the benefits of the natural mapping of the system onto qubits and classical computers’ strength in solving matrix equations.
In QAS, the interactions between particles are broken down into a linear combination of products of Pauli matrices, which are the building blocks for quantum computing operations, while the state itself is split into a sum of simpler states. The quantum portion of the problem then boils down to computing products of basis states with each Pauli term in the interaction. These products are then inputted into the oscillation equations.
Flavor composition (y-axis) of four supernova neutrinos over time due to collective oscillations, calculated using the quantum-assisted simulator. The change in flavor for each neutrino over time shows the effect of neutrino-neutrino interactions.
“Then we get the linear-algebraic equations to solve, and solving such equations on a quantum computer requires a lot of resources,” explains Siwach. “That part we do on classical computers.”
This approach allows researchers to use the quantum computers only once before the actual time evolution simulation is done on a classical computer, avoiding common pitfalls in quantum calculations such as error accumulation over the length of the simulation due to noisy gates. The authors showed that the QAS results for a four-neutrino system match with a pure classical calculation, showcasing the power of this approach, especially compared to a purely quantum simulation which quickly deviates from the exact solution due to accumulated errors from gates controlling two qubits at the same time.
Still, as with any current application of quantum computers, there are limitations. “There’s only so much information that we can compute in a reasonable amount of time [on quantum computers],” says Siwach. She also laments the scalability of both the QAS and full quantum simulation. “One more hurdle is scaling to a larger number of neutrinos. If we scale to five or six neutrinos, it will require more qubits and more time, because we have to reduce the time step as well.”
Harrison, who was an undergraduate physics student at UW–Madison during this project, was supported by a fellowship from the Open Quantum Initiative, a new program to expand undergrad research experiences in quantum computing and quantum information science. She enjoyed her time in the program and thinks that it benefits students looking to get involved in research in the field: “I think it’s really good for students to see what it really means to do research and to see if it’s something that you’re capable of doing or something that you’re interested in.”
Flavor composition of a neutrino over time using a full quantum simulation (red points) compared to exact solution (black line). The points start to drift from the exact solution after only a few oscillations, highlighting how noise in the quantum computer negatively affects the calculation.
Physics major Nathan Wagner awarded Goldwater Scholarship
Posted on
This story is modified from one published by University Communications
Physics and mathematics major Nathan Wagner is one of four UW–Madison students named as winners of 2024 Goldwater Scholarships, the premier undergraduate scholarship in mathematics, engineering and the natural sciences in the United States.
The scholarship program honors the late Sen. Barry Goldwater and is designed to foster and encourage outstanding students to pursue research careers.
“I’m so proud of these four immensely talented scholars and all they’ve accomplished,” says Julie Stubbs, director of UW’s Office of Undergraduate Academic Awards. “Their success also reflects well on a campus culture that prioritizes hands-on research experiences for our undergraduates and provides strong mentoring in mathematics, engineering and the natural sciences.”
The other UW–Madison students are juniors Katarina Aranguiz and Scott Chang and sophomore Max Khanov .
A Goldwater Scholarship provides as much as $7,500 each year for up to two years of undergraduate study. A total of 438 Goldwater Scholars were selected this year from a field of 1,353 students nominated by their academic institutions.
Nathan Wagner (Photo by Taylor Wolfram / UW–Madison)
Sophomore Nathan Wagner of Madison, Wisconsin
Wagner is majoring in physics and mathematics. Wagner began research in Professor Mark Saffman’s quantum computing lab in spring 2021 as a high school junior. His first-author manuscript, “Benchmarking a Neutral-Atom Quantum Computer” was recently accepted for publication in the International Journal of Quantum Information. In Summer 2023, Wagner started research with the Physics Department’s High Energy Physics Group, working alongside Professor Sridhara Dasu and others on future particle colliders design research. Wagner was invited to present his research at the Department of Physics Board of Visitors meeting in fall 2023. This summer, he will complete a research internship at Argonne National Laboratory near Chicago, focusing on computational physics. Wagner plans to pursue a PhD in physics and a career at a U.S. Department of Energy national laboratory researching novel carbon-neutral energy generation, quantum computing and networking, nuclear photonics and computational physics.
About the Goldwater Scholarship
Congress established the Barry Goldwater Scholarship and Excellence in Education Foundation in 1986. Goldwater served in the U.S. Senate for over 30 years and challenged Lyndon B. Johnson for the presidency in 1964. A list of past winners from UW–Madison can be found here.
Undergraduates named 2023 Hilldale Fellows
Posted on
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.
Two students receive Sophomore Research Fellowships
Posted on
Two physics majors have received a UW–Madison Sophomore Research Fellowship as a fellow or honorable mention. The students are:
Erica Magee, Mathematics, Physics; working with Martin Zanni (Chemistry)
Elias Mettner, Physics; working with Abdollah Mohammadi (Physics)
The fellowships include a stipend to each student and to their faculty advisers. Fellowships are funded by grants from the Brittingham Wisconsin Trust and the Kemper K. Knapp Bequest, with additional support from UW-System, the Chancellor’s Office and the Provost’s Office.
Opening doors to quantum research experiences with the Open Quantum Initiative
Posted on
This past winter, Katie Harrison, then a junior physics major at UW–Madison, started thinking about which areas of physics she was interested in studying more in-depth.
“Physics is in general so broad, saying you want to research physics doesn’t really cut it,” Harrison says.
She thought about which classes she enjoyed the most and talked to other students and professors to help figure out what she might focus on. Quantum mechanics was high on her list. During her search for additional learning opportunities, she saw the email about the Open Quantum Initiative (OQI), a new fellowship program run by the Chicago Quantum Exchange (CQE).
“This could be something I’m interested in, right?” Harrison thought. “I’ll apply and see what happens.”
What happened was that Harrison was one of 12 undergraduate students accepted into the inaugural class of OQI Fellows. These students were paired with mentors at CQE member institutions, where they conducted research in quantum science information and engineering. OQI has a goal of connecting students with leaders in academia and industry and increasing their awareness of quantum career opportunities. The ten-week Fellowship ran through August 19.
OQI students attend a wrap-up at the University of Chicago on August 17. Each student presented at a research symposium that day, which also included a career panel from leaders across academia, government, and industry and an opportunity to network. | Photo provided by the Chicago Quantum Exchange
OQI also places an emphasis on establishing diversity, equity, and inclusion as priorities central to the development of the quantum ecosystem. Almost 70% of this year’s fellowship students are Hispanic, Latino, or Black, and half are the first in their family to go to college. In addition, while the field of quantum science and engineering is generally majority-male, the 2022 cohort is half female.
This summer, UW–Madison and the Wisconsin Quantum Institute hosted two students: Harrison with physics professor Baha Balantekin and postdoc Pooja Siwach; and MIT physics and electrical engineering major Kate Arutyunova with engineering physics professor Jennifer Choy, postdoc Maryam Zahedian and graduate student Ricardo Vidrio.
Harrison and Arutyunova met at OQI orientation at IBM’s quantum research lab in New York, and they hit it off immediately. (“We have the most matching energies (of the fellows),” Arutyunova says, with Harrison adding, “The synergy is real.”)
OQI Fellow Kate Arutyunova with her research mentors. (L-R) Engineering Physics professor Jennifer Choy, graduate student Ricardo Vidrio, Kate Arutyunova, and postdoc Maryam Zahedian. | Photo provided by Kate Arutyunova
Despite their very different research projects — Harrison’s was theoretical and strongly focused on physics, whereas Arutyunova’s was experimental and with an engineering focus — they leaned on each other throughout the summer in Madison. They met at Union South nearly every morning at 7am to read and bounce ideas off each other. Then, after a full day with their respective research groups, they’d head back to Union South until it closed.
Modeling neutrino oscillations
Harrison’s research with Balantekin and Siwach investigated the neutrinos that escape collapsing supernovae cores. Neutrinos have a neutral charge and are relatively small particles, they make it out of cores without interacting with much — and therefore without changing much — so studying them helps physicists understand what is happening inside those stars. However, this is a difficult task because neutrinos oscillate between flavors, or different energy levels, and therefore require a lot of time and resources to calculate on a classical computer.
Harrison’s project, then, was to investigate two types of quantum computing methods, pulse vs circuit based, and determine if one might better fit their problem than the other. Previous studies suggest that pulsed based is likely to be better, but circuit based involves less complicated input calculations.
“I’ve been doing calibrations and calculating the frequencies of the pulses we’ll need to send to our qubits in order to get data that’s as accurate as a classical computer,” Harrison says. “I’m working with the circuit space, the mathematical versions of them, and then I’ll send my work to IBM’s quantum computers and they’ll calculate it and give results back.”
While she didn’t fully complete the project, she did make significant progress.
“(Katie) is very enthusiastic and she has gone a lot further than one would have expected an average undergraduate could have,” Balantekin says. “She started an interesting project, she started getting interesting results. But we are nowhere near the completion of the project, so she will continue working with us next academic year, and hopefully we’ll get interesting results.”
Developing better quantum sensors
Over on the engineering side of campus, Arutyunova was studying different ways to introduce nitrogen vacancy (NV) centers in diamonds. These atomic-scale defects are useful in quantum sensing and have applications in magnetometry. Previous work in Choy’s group made the NV centers by a method known as nitrogen ion beam implantation. Arutyunova’s project was to compare how a different method, electron beam irradiation, formed the NV centers under different starting nitrogen concentrations in diamond.
Briefly, she would mark an edge of a very tiny (2 x 2 x 0.5 millimeter), nitrogen-containing diamond, and irradiate the sample with a scanning electron microscope. She used confocal microscopy to record the initial distribution of NV centers, then moved the sample to the annealing step, where the diamond is heated up to 1200 celsius in a vacuum annealing furnace. The diamonds are then acid washed and reexamined with the confocal microscope to see if additional NV centers are formed.
“It’s a challenging process as it requires precise coordinate-by-coordinate calculation for exposed areas and extensive knowledge of how to use the scanning electron microscope,” says Arutyunova, who will go back to MIT after the fellowship wraps. “I think I laid down a good foundation for future steps so that the work can be continued in my group.”
Choy adds:
Kate made significant strides in her project and her work has put us on a great path for our continued investigation into effective ways of generating color centers in diamond. In addition to her research contributions, our group has really enjoyed and benefited from her enthusiasm and collaborative spirit. It’s wonderful to see the relationships that Kate has forged with the rest of the group and in particular her mentors, Maryam and Ricardo. We look forward to keeping in touch with Kate on matters related to the project as well as her academic journey.
Beyond the summer fellowship
Both Harrison and Arutyunova think that this experience has drawn them to the graduate school track, likely with a focus on quantum science. More importantly, it has helped them both to learn what they like about research.
“I would prefer to work on a problem and see the final output rather than a question where I do not have an idea of the application,” Arutyunova says. “And I realized how much I like to collaborate with people, exchange ideas, propose something, and listen to people and what they think about research.”
They also offer similar advice to other undergraduate students who are interested in research: do it, and start early.
“No matter when you start, you’re going to start knowing nothing,” Harrison says. “And if you start sooner, even though it’s scary and you feel like you know even less, you have more time to learn, which is amazing. And get in a research group where they really want you to learn.”
