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MSPQC’s Preetham Tikkireddi wins second place at QED-C student poster presentation

MSPQC student Preetham Tikkireddi won second place for his poster, “Understanding security side channel attacks on multi-tenancy quantum computers,” at the plenary meeting of the Quantum Economic Development Consortium (QED-C), held March 20-21 in Evanston, IL.

Students who attended the plenary first learned best practices for presenting their research to a non-science audience, a useful skill for a cutting-edge field where investors, hiring managers, and policy makers do not necessarily have a quantum background. Then, the students implemented those skills at the judged poster session.

“[The poster session attendees] are really smart people, but they’re not quantum people, so you set them up for asking questions, and based on the questions that they’re asking, you determine how deep you want to go into your research.” Tikkireddi says. “It was a very different kind of experience, rather than just a plain research presentation to a professor or people who already know the field.”

a group of people in business attire stand and pose in a line, they all have nametag lanyards around their necks
A total of 17 students presented posters at the first-ever QED-C student program and poster competition. UW–Madison MSPQC student Preetham Tikkireddi (right) was one of three graduate students to win the top honor at the competition. | Photo credit: QED-C

Tikkireddi’s research, conducted with computer sciences professor Swamit Tannu, looked at the potential for exploiting crosstalk when two users access the same quantum computer at the same time.

“Right now, quantum computers are really expensive, and the way we access them is by sending jobs to these quantum providers like IBM or IonQ,” Tikkireddi explains. “But the queues are really long. If you’re lucky, you can get the results back the next day.”

Quantum computing capacity is growing rapidly in the form of more and more qubits, and most jobs submitted to these long queues do not need to use all the qubits. Tikkireddi and Tannu thought that one way to increase throughput would be to allow users to share the same quantum computer, each using a subset of the qubits. But quantum computations rely on qubit entanglement, where physically separate qubits interact and share information. It was unclear if sharing a quantum computer opens users to security risks.

In his work, Tikkireddi asked if he could count C-NOTs — the gate that is used to create this entanglement — of another user. He entangled two qubits, then asked if two other qubits could “hear” what the first two were doing.

“We were able to use that to figure out how many C-NOTs the other guy is doing. That’s step one of an attack,” Tikkireddi says. “Your algorithm is your intellectual property, so you don’t want people to steal it. It’s a security problem.”

With this initial analysis identifying potential security risks amongst shared quantum computer use, Tikkireddi says providers should currently not let users share computing time, and that future research should focus on ways to mitigate these crosstalk attacks in an effort to balance efficiency with safeguarding intellectual property.

Tikkireddi credits Tannu for helping to guide his poster away from a traditional research poster and toward one more accessible to a non-science audience. He also appreciates the support from MSQPC associate director Katerina Moloni for encouraging and preparing students to take advantage of these training opportunities.

“It was a really good networking opportunity, especially for me, who is looking for a job right now,” Tikkireddi says. “I would highly recommend students to go to these kinds of events because we get a chance to interact with people in the industry.”

WIPAC researchers set new limits on the origins of the Galactic neutrino emission detected by IceCube

Neutrinos are tiny, nearly massless particles that travel cosmological distances unhindered, acting as messengers that carry information about their sources. Since the recent detection of high-energy neutrino emission from the Milky Way, the IceCube Neutrino Observatory at the South Pole is working to pinpoint the exact nature of the Galactic emission contributing to the astrophysical [...]

Read the full article at: https://wipac.wisc.edu/wipac-researchers-set-new-limits-on-the-origins-of-the-galactic-neutrino-emission-detected-by-icecube/

Welcome, Professor Tiancheng Song!

Photo of Tiancheng Song
Tiancheng Song

Tiancheng Song, a condensed matter experimentalist, joined the UW–Madison Physics Department as an assistant professor on May 20. His research interest lies in two-dimensional (2D) quantum materials with a focus on 2D magnetism, 2D superconductivity and 2D topology. He joins us from Princeton University where he was a Dicke Fellow and won the Lee Osheroff Richardson Science Prize. He completed his PhD at the University of Washington and his bachelor’s degree from University of Science and Technology in China. He is originally from Tianjin, China, the son of two theoretical physicists.

Please give an overview of your research.

I work on experimental condensed matter physics and am especially interested in a new family of materials called two-dimensional materials, which resemble “Quantum LEGOs” at the atomic scale. These 2D materials can be exfoliated down to the monolayer limit just using Scotch tape, and each monolayer can act like a LEGO piece. This provides us with a full LEGO set of quantum materials in two dimensions, covering a broad spectrum of emergent quantum phenomena. Within this new material platform of condensed matter physics, I’m particularly interested in three topics: magnetism, superconductivity and topology. With the new tuning knobs uniquely enabled in this new material system, we aim to study these three topics in two dimensions using those LEGOs. There will be a lot of fun because we can use them like building blocks, stack them together like LEGO toys, and uncover new physics emerging from the toys we create!

What are the first one or two research projects you’ll work on when your group is running here?

Overall, we plan to discover new 2D quantum materials, develop new measurement techniques and explore new physics in this emergent platform. We aim to combine state-of-the-art nanofabrication of 2D materials with various measurement techniques including magneto-optics, quantum transport, thermoelectrics, optoelectronics, optical spectroscopy and microscopy. Our research will explore three directions: 2D magnetism, 2D superconductivity and 2D topology.

What attracted you to Madison and the University?

The University of Wisconsin–Madison is a top public university located in a beautiful city. The Department of Physics is renowned for its exceptional research in many areas of physics. My partner also works at UW–Madison.

What is your favorite element and/or elementary particle?

I usually say Chromium or Tellurium, but this time I would say Technetium (symbol Tc and atomic number 43). This is because my name is Tiancheng, and when I was a kid, my parents called me TC just for fun. Since studying abroad, I have found my name sometimes difficult to pronounce and remember for others, because it is a bit long and complicated. So, I started using this nickname again, and I’m happy to be called TC!

What hobbies and interests do you have?

I enjoy many sports, such as badminton, tennis and swimming. For those other sports that I am not very skilled at, I enjoy watching rather than playing.

Ke Fang named inaugural recipient of the Bernice Durand Faculty Fellowship

The Department of Physics is pleased to announce that Ke Fang, assistant professor of physics and WIPAC investigator, has received the inaugural Bernice Durand Faculty Fellowship. This fellowship, given in honor of late Professor Emerit of Physics Bernice Durand, recognizes Fang’s major contributions to the analysis of data from the NASA Fermi satellite, the High Altitude Water Cherenkov (HAWC) telescope and IceCube, and for fundamental theoretical insights in their multimessenger context. Fang is a Sloan Fellow, has been awarded an NSF CAREER award, and is the spokesperson for the HAWC experiment.

a man and a woman smile while both holding a framed award certificate
Department Chair and professor Mark Eriksson (left) presents assistant professor Ke Fang with the Bernice Durand Faculty Fellowship at the department awards banquet in May 2024.

Durand was one of the first two women professors in the UW–Madison Department of Physics. While at UW–Madison, Durand was a theoretical physicist who specialized in particle theory and mathematical physics. Her research was on symmetry relations in algebra and physics, plus the phenomenology of high-energy interactions at large particle accelerators.

As the first Associate Vice Chancellor for Diversity & Climate, Professor Durand provided leadership to ensure that faculty, staff, and student diversity issues including race, ethnicity, gender, sexual preference, and classroom and general campus workplace climate issues be addressed, and that search committees for non-classified staff be trained in broadening the pool of applicants and eliminating implicit bias. Durand co-directed a grant from the Alfred P. Sloan Foundation to the UW System designed to create more equity, flexibility and career options for faculty and academic staff. She was also a member of the leadership team of the Women in Science and Engineering Leadership Institute sponsored by the National Science Foundation to increase the participation and status of women in science.

A recipient of the Chancellor’s Award for Outstanding Teaching, Professor Durand taught courses at all levels, from modern physics for non-scientists (“Physics for Poets”) to a specialized course she developed for advanced graduate students in the use of topology and algebra in quantum field theory. In the mid 1990s, she used technological and pedagogical techniques in her teaching, such as broadcasting her modern physics for non-scientists course on public television with web-based coursework, and pioneering one of two early versions of MOOCs (massive open online courses) on campus.

Durand passed away in 2022.

The Bernice Durand Faculty Fellowship was conceived by our Board of Visitors, who spearheaded the ultimately-successful fundraising effort, with support from Professor Emerit Randy Durand for this fellowship honoring his wife.

Cristian Vega awarded Callen Award for Excellence in Theoretical Plasma Physics Research

profile picture of Cristian Vega
Cristian Vega

Congrats to (now) Dr. Cristian Vega who won the Callen Award for Excellence in Theoretical Plasma Physics Research! Vega won the award on April 29, just days before defending his thesis on May 3.

The Callen Award is awarded annually to a UW–Madison plasma physics graduate student for achievements in plasma theory. Now-retired Professor Emeritus Jim Callen was a long-time faculty member in the Nuclear Engineering and Engineering Physics department. Callen was also an affiliate faculty member of the Physics department.

Two physics students win presentation awards at APS April Meeting

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.

profile photo of Elias Mettner
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.

a woman stands in front of a screen with a powerpoint presentation title slide showing
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.

Pupa Gilbert earns undergraduate mentoring award

Congrats to Prof. Pupa Gilbert on earning an Award for Mentoring Undergraduates in Research, Scholarly and Creative Activities!

The Office of the Provost offers awards to recognize the important role mentors play in fostering undergraduates’ intellectual, personal and professional growth through participation in high-impact practices including research, scholarly and creative endeavors. These awards provide mentors with recognition for their excellence in mentoring undergraduates and their contribution to our students’ Wisconsin Experience.

Gilbert has mentored many undergraduate and graduate students as a physics professor at UW–Madison. Some of these students, like Andrii Hopanchuk ‘24, worked on individual research projects and served as an undergraduate teaching assistant for her popular course, Physics 109, Physics in the Arts.

“Pupa has supported me in exploring my own work, which ultimately culminated in me single-authoring a paper and publishing it in a peer-reviewed journal,” Hopanchuk wrote in his nomination letter. “Another way Pupa has impacted my professional growth was by maintaining a high standard for me (I wish more people did that).”

In 2020, when in-person undergraduate student research positions were almost non-existent, Gilbert had an idea to hire over a dozen students, largely from the Mercile J. Lee Scholars program, to conduct remote analysis on complicated data sets. Machine learning models are only as good as the data they are trained on, and Gilbert reasoned that a large group of diverse students conducting parallel analyses would yield conclusions that computers never could.

This group of 15 students, dubbed the Cnidarians (from the phylum that includes corals, anemones, and jellyfish — animals these students analyzed in Gilbert’s group), each processed the data, making 11 distinct decisions along the way. At weekly Zoom meetings, results were compared. If the majority of Cnidarians agreed on a solution, it was likely the correct one; if not, the students walked others through the process of how they made the decisions they did.

“We (the Cnidarians, really!) discovered many ways to improve data processing,” Gilbert wrote in a Springer Nature “Behind the Paper” feature. “Diversity is our strength. The accuracy, precision, and overall quality of the results is outstanding and unprecedented.”

Many Cnidarians were among Gilbert’s nominators for the Mentoring award.

“Pupa is one of the few professors I have experienced whose energy for learning is contagious – any student under her mentorship is bound for success,” wrote Virginia Quach ’23, now a Pharmacy doctoral student.

Isabelle LeCloux is a senior chemical engineering major who worked with Gilbert both at UW–Madison and at Lawrence Berkeley National Lab this past summer. She wrote:

“Working with other undergraduates in the welcoming and encouraging environment fostered by Professor Gilbert has allowed me to explore topics that I otherwise would not have been exposed to in my curriculum. Her positive attitude makes her a delight to work with and I always feel that I can ask any questions I may have regarding our work in the group.”

Biology major CP Breit joined the Cnidarians after they had already been working together for a year, but she said that Gilbert made it easy to join the already-established team.

Breit wrote: “During this training period Dr. Gilbert was incredibly supportive and really gaveme the confidence to start processing data quickly. There were certainly shortcomings in my technical acumen but Dr. Gilbert was always positive and encouraging, allowing me to make mistakes, learn how to correct them, and improve.”

All the Cnidarians were named as co-authors on the Gilbert group’s most recent paper, published in February in the prestigious journal Nature Communications. Other Cnidarians co-authored a 2022 JACS paper.

Gilbert and other mentoring awardees were recognized at the Mentor Awards Ceremony held during the annual Undergraduate Research Symposium on April 25.

a group of people stand on a stage, all holding framed certificates
The 2024 Mentor award winners at the Undergraduate Research Symposium. Pupa Gilbert is in the front row, third from right (photo provided by Pupa Gilbert)