Distinguished University Professor Ed Ott Retires

Distinguished University Professor Ed Ott retired in December, having served on the UMD faculty for a remarkable and stellar 43 years. Ott is globally known for his pioneering contributions in nonlinear dynamics and chaos theory. 

"Ed has had a magnificient career, exploring and explaining chaos and helping researchers to understand its impact across disciplines," said Physics chair Steve Rolston. 

In recent years, Ott was instrumental in sparking intense activity in applying machine learning to nonlinear dynamics, giving keynote lectures and invited talks in several countries. For the AIP journal Chaos he was asked to co-edit a special 2020 issue: When machine learning meets complex systems: Networks, chaos, and nonlinear dynamics.

Ott, a member of the National Academy of Sciences, is a University of Maryland Distinguished University Professor and holder of the Yuen Sang and Yu Yuen Kit So Endowed Professorship in nonlinear dynamics. He received the 2014 Julius Edgar Lilienfeld Prize of the American Physical Society, and in 2016, with  Celso Grebogi and James A. Yorke, was named a Thomson Reuters Citation Laureate in physics for "...development of a control theory of chaotic systems."

In 2017,  Ott received the Lewis Fry Richardson Medal of the European Geosciences Union for pioneering contributions in the theory of chaos.  Also in 2017, he was selected for the Jürgen Moser Lecture and Award, of the Society for Industrial and Applied Mathematics "... for his extensive and influential contributions to nonlinear dynamics, including seminal work on chaos theory and on the dynamics of physical systems." He was elected a foreign member of the Academia Europaea for his outstanding achievements and international scholarship as a researcher.  

Ott is a Fellow of the Society for Industrial and Applied Mathematics, the American Physical Society and the Institute of Electrical and Electronics Engineers.  He has served as an editor or editorial board member for most renowned journals in his field, including Physica D, Physical Review Letters, Physics of Fluids, Physical Review, Chaos and Dynamics and Stability of Systems.  

Ott received his B.S. in Electrical Engineering at The Cooper Union and his M.S. and Ph.D. in Electrophysics from the Brooklyn Polytechnic Institute, then enjoyed a postdoctoral fellowship at the Department of Applied Mathematics and Theoretical Physics of Cambridge University. Upon his return to the U.S., he joined the Electrical Engineering faculty at Cornell. He left Ithaca in 1979 to join the Department of Physics and Department of Electrical Engineering on this campus. He is a member of the Institute for Research in Electronics and Applied Physics (IREAP), and has held appointments at the Naval Research Lab and what is now the Kavli Institute for Theoretical Physics at the University of California, Santa Barbara. 

In addition to more than 500 papers, Ott has written the book "Chaos in Dynamical Systems", and edited "Coping with Chaos,"  a collection of reprints that focuses on how scientists observe, quantify, and control chaos.   He has advised more than 50 doctoral students, starting with Distinguished University Professor Tom Antonsen at Cornell University (1977) and most recently including Amitava Banerjee (2022).

 

From Physics to Pharma

Sylvie Ryckebusch (B.S. ’87, physics; B.S. ’87, mathematics) has never underestimated the value—or the challenges—of earning a physics degree.

“I think physics is the hardest subject really,” she explained. “It trains your problem-solving skills, the way you think and learning to work on difficult things. When you’ve spent years studying physics, I think it trains you well for many other lines of work.”Sylvie RyckebuschSylvie Ryckebusch

Ryckebusch applied these skills on a rewarding academic and professional path that took her from the research lab to the business world, and from the U.S. to Europe and beyond. Over the past 20 years, she built an impressive track record leading business development for biotech and pharmaceutical companies, negotiating complex research collaborations and licensing transactions, and specializing in everything from partnerships and corporate strategy to helping bring new therapeutics to market. 

Today, as chief business officer at BioInvent International in Lund, Sweden, Ryckebusch supports the company’s efforts to develop new antibody drugs for the treatment of cancer. And though she didn’t exactly plan it this way, she’s exactly where she wants to be.

“People always ask me, ‘How did you organize your career to end up in business development?’ because that’s a place where a lot of people want to be—in the pharma industry, and most particularly, in business development” she said. “Honestly it was mostly happenstance. One thing led to another and another and I ended up here, although what was important in making these career choices was the self-awareness along the way about what kind of work and environment I enjoyed.”

European roots and a strong work ethic

Growing up in Howard County, Maryland, Ryckebusch always felt a strong connection to her European roots. Her parents immigrated to the U.S. from France before she was born. 

“My mother was a secretary at the World Bank and my father was a chef,” she explained. “He grew up during the war in very difficult times in northern France and had to be pulled out of school early to help support the family, so he became an apprentice in a restaurant. When I was growing up, he was working around the Washington area as a chef and had his own restaurant for a time in Ellicott City.”

With many of her relatives still living in France, Ryckebusch decided to spend her high school years there. Fluent in French, she was interested in many subjects, but her teachers pushed her to pursue her strengths in mathematics.

“If you’re good at science, people aren’t going to tell you that you should study English literature,” Ryckebusch said. “I was always good at math and science and in the schools in France, if you’re good in math they tell you that’s what you’ve got to do, they push you.”

Ryckebusch returned to the U.S. after high school and began college at the University of Maryland in 1983, taking on the challenges of a double degree in mathematics and physics. Raised with a strong work ethic, she was driven to keep doing more. 

“I made it really hard for myself,” she admitted. “I skipped the first-year courses, which I probably shouldn’t have done and I did a double-degree program, which would have been a five-year program, but I did it in four years. So, what I remember most from my UMD time is working really hard.”

In those intense academic years, Ryckebusch spent her summers working with a low-temperature physics group at Bell Labs. After graduating from UMD in 1987, she moved on to a Ph.D. program in computation and neural systems at Caltech. 

“My focus was understanding the control of locomotion by the neural system,” she explained. “I was, on the one side, building integrated circuits, transistors and capacitors, the circuits that modeled certain behaviors of neurons in the brain, and in parallel, I was doing actual experiments to identify neuronal circuits involved in locomotor functions.”

After earning her Ph.D. in 1994, and a postdoctoral fellowship at Brandeis University, Ryckebusch was ready for something new. 

“I had to weigh doing academic science for a career or at least the next six or seven years or starting something different, and I thought, I want a change,” she explained. “I like variety and I wanted to be in the real world, though I wasn’t really sure what the real world was.”

Encouraged by a friend, Ryckebusch joined the Harvard Business School as a postdoctoral researcher. There, she investigated business operations, developing case studies on companies all over the world, some of which are still taught at HBS today.

“I went to Japan, to Israel, all over the place, exploring particular issues related to businesses and the organization of their work and writing these up in case studies,” she recalled. “It was different and it was fun, and I fell into it very easily.”

From case studies to consulting

In 1996, Ryckebusch’s academic background, business research at Harvard and fluency in French helped her land a management consulting position at the Paris office of global consultants McKinsey & Company. The experience helped strengthen her skill set in corporate strategy and business development, but after four years, she realized she missed working with scientists and the intricacies of scientific problem-solving.

“I thought this has been fun and I learned so much, but it was very hard work and not really who I was” Ryckebusch explained. “I wanted to get back into a career closer to science.”

Hoping to apply her experience in both science and business, Ryckebusch joined Serono, a large Geneva, Switzerland-based biotech firm. She quickly realized it was the right place at the right time.

“I ended up in the very best possible place for me and I loved it,” she recalled. “You’re negotiating partnerships and alliances—pharma-pharma, pharma-biotech, biotech-academia alliances—and you have to have a good grasp of the science because you’re working on drug development. It was a business role that I’m still doing today over 20 years later.”

Pharmaceutical giant Merck eventually acquired Serono and shut down its Geneva office, but by then Ryckebusch had three kids in school and didn’t want to uproot her family. So, in 2012, she started her own consulting business. Based in Geneva, she worked with pharma and biotech clients, even finding time to teach a graduate-level pharmaceutical business development course at the Grenoble Ecole de Management.  

Then in early 2020, one of Ryckebusch’s clients, BioInvent, suggested that she join them full time as chief business officer.

“BioInvent is a super company, with very high quality science and promising therapeutic drug candidates. I was doing more and more work with them, and they said, ‘Why don’t you join us,’ and it just made sense,” Ryckebusch recalled. “So that’s what I’m doing now.”

Part of a bigger mission

As BioInvent’s chief business officer, Ryckebusch works remotely from her home in Geneva, leading business development efforts, building partnerships and research collaborations for drug development, as well as supporting the investor-backed company with financing and company strategy.

“It costs $800 or $900 million to develop a pharmaceutical product, so biotechs almost never take them to market on their own, you have to partner with a big pharma at some point,” she explained. “There’s a whole strategy around how you partner, when you partner and with whom.”

Ryckebusch takes pride in her role as part of BioInvent’s scientific work in cancer therapeutics. But she’s quick to note that she’s just one small part of a much bigger mission.

“I enjoy that feeling of collectively bringing something forward—we’re all cogs in a wheel,” she explained. “In the pharma industry, it takes 15 to 20 years to develop a drug and a lot of people like me contribute along the way.”

For Ryckebusch, making that kind of contribution means everything.

“It’s all about finding great drugs and developing them and pushing the frontiers of the science,” she reflected. “I really hope one of BioInvent’s products makes it to the market. I would be proud to be able to say a little bit of that came from me.”

Recent Alumnus Embraced Community and Service at UMD

Joining a graduate program is not just about choosing a university and studying a subject. It’s also about joining a community of people who help shape the experience and can support and welcome people who are new to the world of academic research.

Andrew Guo (Ph.D. ’22, physics) spent a lot of his time at UMD researching the underpinnings of quantum interactions and algorithms as a graduate student at the Joint Quantum Institute and the Joint Center for Quantum Information and Computer Science (QuICS). During that period he also made time to connect with surrounding communities and to invite other people to participate in physics and astronomy research through the graduate student organization called Graduate Resources for Advancing Diversity with Maryland Astronomy and Physics (GRAD-MAP).

Andrew Guo teaching a lesson as part of the 2018 ASDAN Math Tournament in Beijing, China.Andrew Guo teaching a lesson as part of the 2018 ASDAN Math Tournament in Beijing, China.Guo credits his choice to study physics to a natural spark of curiosity, along with his childhood enjoyment of math and science. 

“Physics in particular inspired me, both because of its elegance and simplicity and its ability to have a huge impact on society,” Guo said. “For me, personal curiosity was a big factor. But also, knowing that there's potential societal impact as a result of research was a key motivating factor.”

Before coming to UMD, Guo studied physics as an undergraduate at Stanford University, where he became particularly intrigued by quantum information and quantum computing. 

“I thought UMD was doing great work at that area from sort of the full stack—from experimental trapped ion quantum computing all the way up to the theoretical complexity theory side,” Guo said. “So, I wanted to dive in, and they offered me a fellowship through QuICS, which I've been affiliated with through all my six plus years here. And I think I found a great community there.”

 Andrew Guo with three other recipients of QuICS Lanczos Graduate Fellowships. From left to right: Aniruddha Bapat, Minh Tran, Andrew Guo, and Eddie Schoute.  Image credit: Arushi Bodas Andrew Guo with three other recipients of QuICS Lanczos Graduate Fellowships. From left to right: Aniruddha Bapat, Minh Tran, Andrew Guo, and Eddie Schoute. Image credit: Arushi Bodas

After Guo decided to come to UMD, he hadn’t settled on exactly what aspects of quantum research to focus on, and there were several professors he was open to working with. Alexey Gorshkov, an adjunct associate professor of physics at UMD, approached him about research into long-range interacting systems. This research looked at how interactions between quantum particles that aren’t immediate neighbors influence the spread of the property called quantum entanglement and can speed up quantum computations. 

“I was excited that I was able to get such an outstanding student,” Gorshkov said. “It was fantastic, from both the research aspect and the mentoring service aspect. He did well in both, wrote excellent papers, and also was very helpful to other people in the group.”

Pursuing the line of research, Guo and his colleagues were able to make several advances, including identifying how speed limits for quantum information can depend on the particular task and making a protocol that achieves the theoretical speed limit for certain tasks.

“I found it very, very helpful to have close collaborators—people to talk to who can help you when you're stuck, who can bounce ideas off each other,” Guo said. “It was a pleasant surprise to find that the collaborative environment at Maryland was such an integral part of grad school.”

While beginning graduate research, Guo also wanted to do community outreach. Guo learned about GRAD-MAP during his first year at UMD, when one of the organization’s leaders gave a presentation to the physics graduate students. GRAD-MAP is dedicated to promoting diversity, equity and inclusion in the fields of physics and astronomy. The organization strongly focuses on reaching out to students with backgrounds that are underrepresented in physics and astronomy and bringing them to UMD to share valuable experiences in the field. 

“We are grad students working to promote inclusive environments for fellow grad students, as well as increase the proportion of students who come from underrepresented minority backgrounds,” Guo said. 

GRAD-MAP organizes programs to give undergraduate students insight into the world of physics and astronomy research and help them develop useful skills. The organization runs a weeklong Winter Workshop where undergraduates tour scientific facilities, perform mini-research projects and develop skills, such as writing application essays and computer programing. GRAD-MAP also organizes a 10-weeks-long Summer Scholars Program where undergraduate students can build on the Winter Workshop skills with a full research project under the supervision of a mentor. GRAD-MAP has worked with students from nearby institutions like Prince George’s Community College, Montgomery College and Howard University, as well as students from across the U.S. and outside the country.

Guo’s first January at UMD, he taught the programming language Python at the Winter Workshop. He said he was inspired by the students and kept teaching programing as part of GRAD-MAP. He eventually worked his way up to leading the entire Python portion of the workshop.

“For these students to learn programming, I think is pretty significant because it gives them a playground to test their ideas,” Guo said. “And it's very good practical training for them, regardless of what career they pursue in the future, be it physics or astronomy grad school or even a career as a software engineer.” 

In the fall of 2019, he became the physics co-lead of GRAD-MAP. Then, in the face of the coronavirus pandemic, he had to pivot the program. The GRAD-MAP graduate students transitioned their outreach events online for their 2020 and 2021 Winter Workshops and 2020 Summer Scholars Program.

“A lot of credit goes to my fellow graduate colleagues who really stepped up,” Guo said. “The biggest challenge was to replicate that sense of community online, without leading to basically Zoom fatigue and burnout among the students. I think the students really were the ones who put in the most heroic effort—just going through enduring and then sticking with us as we performed this huge experiment that everybody was doing at that time.”

 

Andrew Guo and his co-leads Milena Crnogorčević and Charlotte Ward on a video chat with five participants of the 2021 Summer Scholars Program. Andrew Guo and his co-leads Milena Crnogorčević and Charlotte Ward on a video chat with five participants of the 2021 Summer Scholars Program. Despite the additional stress, Guo fondly recalled a GRAD-MAP video chat event where the Winter Workshop participants could show off talents, like playing an instrument, or share other things they cared about, like a participant discussing their plant terrarium. Guo said seeing both the engagement and lasting impact on the students from the program was very fulfilling.

During his time at UMD, Guo also joined communities outside of GRAD-MAP and his lab group. Throughout his time at UMD he lived with other physicists. 

“It was definitely a uniquely collaborative, uniquely enriching experience for me,” Guo said. “Throughout COVID not being able to see your coworkers in person made this all the more valuable because you could have informal conversations.”

He also played the cello as a member of the UMD Repertoire Orchestra (now rebranded as the University Orchestra), which is open to members of the campus community, including students from non-music degree programs. He said participating in that creative expression was a nice pressure valve.

Next, Guo will be joint a new community at Sandia National Laboratories as a postdoctoral researcher and said he hopes to participate in outreach efforts there. 

 

Story by Bailey Bedford

Related news stories: 

https://jqi.umd.edu/news/new-quantum-information-speed-limits-depend-task-hand

https://jqi.umd.edu/news/new-approach-information-transfer-reaches-quantum-speed-limit

Rehearsals, Recitals and Research

University of Maryland physics and astronomy dual-degree senior Delina Levine got her first introduction to music when she just was six years old, soon after she pestered her parents to sign her up for piano lessons. Delina LevineDelina Levine

As her fingers rhythmically tapped the black and white keys, Levine noticed that the sounds she created with the piano differed depending on the amount of force her hands exerted on the keys. Applying the piano’s pedals while she played created variations in the sounds she produced and while some chords harmonized, others didn’t. It wasn’t until years later that she learned why and how these changes influenced the music she played.

In middle school, her teacher asked the students to write a paper on any topic, so long as that topic tied back to math. Although Levine was skeptical, her teacher assured her that there was a mathematical connection to almost anything she could think of. 

“Of course, I chose to write about music for that assignment,” Levine recalled. “I wasn’t sure at first, but when I researched for the paper, I got to learn about the relationship between math, physics and music. What really struck me was how physics is so involved in music, especially with concepts like acoustics. It was then that I realized how important physics is when it comes to understanding how things work.”

After that assignment, Levine believed physics could be the key to satisfying her natural inquisitiveness about music, stars and outer space. At UMD, Levine’s trifecta of interests prompted her to pursue a dual degree in astronomy and physics in addition to a minor in music performance. 

“My first year here, I attended a class taught by Professor Bhatti that talked about the detection and analysis of dark matter. I remember that the class made a big impression on me,” Levine explained. “That was a big step for me into the overlap between physics and astronomy.”

Levine also participated in the 2020 Student Summer Theoretical Physics Research Session (SSTPRS), a program developed by Distinguished University Professor of Physics S. James Gates Jr. Designed to introduce undergraduates to the world of experimental physics research, SSTPRS provided Levine’s first opportunity to see real-world applications for the science she learned in the classroom. 

“We spent the first few weeks learning the math and physics needed for the calculations we needed to make later in the program,” said Levine. “That summer, I worked on supersymmetry projects with a group of other undergrads like me, and it gave me critical insight into research and all of the collaborative effort behind it.”

According to Levine, UMD’s Society of Physics Students (SPS) has also been one of the most instrumental parts of her journey to becoming a full-fledged researcher. As a member since 2019, Levine participated in exclusive behind-the-scenes lab tours led by professors and industry physicists, professional development workshops and training sessions, field trips to the campus nuclear reactor and movie nights. In her sophomore year, Levine served as SPS board communications officer. By fall 2022, she was elected president—taking a leadership role in the organization that guided her since the beginning of her journey in physics. 

“All the camaraderie and knowledge-sharing that I experienced with SPS inspired me to get more involved with its activities and leadership,” Levine said. “I just wanted to continue that tradition and remind my peers that we’re all in this together.”

"As SPS president, Delina is an inspiring leader,” said Donna Hammer, SPS faculty advisor and director of education for UMD’s Department of Physics. “Her vision for SPS includes providing the opportunity for every physics major to feel included, informed and supported.”

Off-campus, Levine puts the skills she developed at UMD into practice. She currently works as an undergraduate research assistant at the National Astronomical Observatory of Japan (NAOJ), where she studies gamma-ray bursts. Since she started her remote position with NAOJ in 2021, Levine has already written on gamma rays, their luminosity and their potential to be used as a way to measure cosmological distances. 

“Although my work at NAOJ is done online, the research environment I’m part of is incredibly diverse. My colleagues are from different time zones and countries all over the world—Italy, India, Japan, just to name a few. I also have a female principal investigator, which is still a rare occurrence in the world of physics and astronomy,” Levine said. “I see her as a role model and mentor, and I’d like to become someone like that in the future for other young scientists. What I’ve learned from NAOJ and also UMD makes me feel better equipped to tackle future challenges and goals that may come to me as a researcher."

Despite her busy schedule, Levine continues to make time for music. Over the years, she accompanied choirs and played with jazz bands, which she says helped her explore her talents beyond her classical training and develop additional layers of flexibility. In May 2022, Levine performed a piano recital at the Clarice Smith Performing Arts Center to an audience full of her peers, something she hopes to do again before she graduates in May 2023. 

“Having these experiences with SPS, my music and my research is very fulfilling for me. I especially appreciate the collaborativeness, creativity and diversity of thought that all these parts of my life encourage,” Levine said. “As president of SPS, I really want to continue supporting my fellow physics students with more opportunities to support and learn from each other—just as SPS and my mentors have done for me.” 

Nathan Schine Twists Photons and Cools Atoms in a Unique Quantum Dance

Deepening our understanding of the quantum world and developing new tools to peer into it is a very active area of physics research today. In this crowded field full of diverse theoretical ideas and physical tools, Assistant Professor and JQI Fellow Nathan Schine has managed to carve out a distinctive space for himself and his lab.Nathan SchineNathan Schine

Schine’s research program manipulates the interactions between atoms and photons—the particles that make up light—in novel, well-controlled ways in order to simulate other, harder-to-probe quantum phenomena. To coax the photons into new simulation patterns, Schine is using unique arrangements of mirrors to bounce photons around. He is also strategically placing atoms in the photons’ way with the help of precisely controlled laser beams. To boot, the atoms he is using (ytterbium) have a relatively complex structure, giving Schine extra avenues to explore. He has been able to create this unique niche by combining the experimental expertise he gained from graduate school and postdoctoral research with his theoretical big-picture savvy.

Schine has been slowly homing in on his academic sweet spot for much of his life. Growing up, his interests were broad—they included science and math, but also history and other areas of the humanities. “It wasn't like I knew from an early age that I was going to go be a physicist,” Schine says.

Science wasn’t outside the realm of Schine’s imagination, however. His father was a chemistry teacher, his mother had a degree in math, and his grandfather was a physics professor at Vanderbilt University. 

Keeping his options open, Schine attended Williams College. Ranked first among U.S. liberal arts colleges by U.S. News and World Report, Williams boasts an unusually strong science and math program. Schine was interested in math, but eventually found it to be too abstract for his taste. “When math got into proving the existence of a solution to a problem and not actually solving the problem, I sort of lost the thread a bit,” he recalls. Instead, he found that the part of math he enjoyed most could be gotten through physics, so he dove deeper into the subject. 

An undergraduate research project sealed the deal for Schine as a physicist and experimentalist. He started working in the lab of his soon-to-be quantum mechanics professor, Barclay Jermain Professor of Natural Philosophy at Williams Protik Majumder, midway through his sophomore year.

Under Majumder’s supervision, Schine started to get a taste for experimental physics. He was performing spectroscopic measurements on indium atoms as a sophomore and continued working with Majumder until he graduated. Indium, with its three loosely bound, outermost electrons, is hard to model theoretically, and Majumder’s lab collaborated with theorists to benchmark their calculations and zero in on precise values. 

Schine relished the chance to make a real contribution to the project. He also found joy in tinkering in the lab, finding his calling as an experimentalist. “I liked the day-to-day aspects of it, the actual process of building a laser or something,” Schine says. “A lot of it is very tactile and building up this sort of Rube Goldberg device that happens to be useful for physics—that, I think, is a lot of fun.”

Majumder had a slightly different take on what set Schine apart in his lab. “He was really unusual, even as a 20-year-old, in being able to balance comfortably the very hands-on build stuff with the bigger intellectual picture, which is obviously something that's been characteristic of his career since then,” Majumder says. Schine’s research with Majumder culminated in a senior thesis and a peer-reviewed publication

Schine was inspired by his undergraduate research experience and decided to pursue graduate school. His chops setting up lasers and other experimental equipment meant he could hit the ground running and start contributing right away to the brand-new lab of Jonathan Simon at the University of Chicago. 

The lab Simon was envisioning involved filling an optical cavity—a set of mirrors trapping light and bouncing it back and forth between them—with ultracold rubidium atoms. The idea was to use the photons themselves as a quantum playground, used to re-create and study quantum phenomena that happen in other, less accessible settings. 

A lot of the interesting quantum phenomena that appear in real materials are hard to peer into at the quantum level but are nevertheless important for our daily lives because of their ubiquitous applications in technology. In Simon’s lab, precisely controlled photons can play a similar role to electrons inside of a material. Studying how these photons behave in a cavity and measuring them directly can then give clues about what happens inside the chunks of material. 

There is one obvious limitation for photons playing the part of electrons: They don’t have an electric charge. And charged electrons—specifically in magnetic fields—are responsible for a range of interesting material effects that might need simulating. 

Back in the early 1980s, physicists discovered one such effect.  A thin layer of semiconductor placed inside a strong magnetic field was found to conduct electricity in very precise chunks. As the magnetic field is increased, the conductivity doesn’t change for a while—it stays at one plateau—and then hops abruptly to another plateau. This is known as the integer quantum Hall effect (IQHE) because the plateaus appeared at very regularly spaced integer values.

Even more strangely, for very cleanly engineered semiconductors, experimentalists found sub-plateaus within the plateaus, appearing at precise fractions of the previous integer values. They termed this, predictably, the fractional quantum Hall effect (FQHE). The origins of these fractional plateaus are largely still a mystery, although physicists are pretty certain that it has something to do with interactions between electrons giving rise to unexpected collective behaviors. If there was a way to simulate the full quantum theory of the FQHE, it might reveal new insights into what’s going on. 

Simon and Schine, along with their labmates, hatched a plan. They conceived of a new way to make photons behave as though they have charge and live in a magnetic field that could, in principle, allow the photons to interact with each other and simulate the FQHE. Their plan involved a wonky cavity: four mirrors aligned to bounce light around in a twisted bow-tie configuration over and over again, with one of the mirrors slightly askew, as in the diagram shown below.

Photons and atoms in Schine’s tilted bow-tie cavity. (Credit: Nathan Schine/JQI)Photons and atoms in Schine’s tilted bow-tie cavity. (Credit: Nathan Schine/JQI)

Schine and his labmates focused on what happened along a plane at the center of this cavity. There, the photons were analogous to electrons traveling inside a thin material like in either of the Hall effects. The twisted mirror configuration causes the photons to twist around, much like electrons precess around inside a magnetic field. 

With careful cavity design, they were able to make the analogy come to life and make their photons replicate the IQHE in its full glory. They published this result in the journal Nature

To go beyond integer quantum Hall physics, the particles need to interact with one another—not just pass through each other, like photons are wont to do. That’s where atoms entered the picture. Previously, scientists had worked out a technique that allows atoms to serve as an intermediary through which photons can talk to each other. 

In parallel with the twisted cavity work, Simon’s lab had been working on this atom-assisted approach to making photons interact with each other. This involved cooling a gas of rubidium atoms to extremely low temperatures, just a touch above absolute zero. Then, the light was tuned to a particular color that would allow one of the rubidium atoms to absorb a single photon. This atom then prevented any nearby atoms from absorbing a photon, ensuring no other photon got too close. This created an effective interaction between photons, where they were averse to being too close to one another. 

The next step was to combine the two techniques: put the rubidium inside the skewed bowtie cavity. The cavity makes photons act like electrons in a magnetic field, and the atoms create a medium through which the photons can interact. The combination created the right conditions for FQHE physics. Although short-lived, the photons in Schine’s experiment appeared to indeed exhibit the hallmarks of fractional quantum Hall physics. Schine and his labmates published this result in the journal Nature

This was the first time the fractional quantum Hall effect had been simulated in any medium. For his graduate work, Schine was named a finalist for a thesis prize from the American Physical Society’s Division of Atomic Molecular and Optical Physics, the most prestigious thesis award in this field. 

Schine was still circling around his ultimate niche, though, and he sought to broaden his experimental skillset during his postdoctoral studies. He joined the group of Adam Kaufman at JILA at the University of Colorado Boulder (sometimes snarkily called JQI West). Kaufman’s lab manipulates atoms with light, using a tool called optical tweezers—laser beams focused down to a very narrow spot, intense enough to hold an atom in place. 

Schine, Kaufman, and collaborators used these optical tweezers to put a new spin on atomic clocks, which are the most precise timekeepers we have. They work by counting the intrinsic ticking of individual atoms. Precise as they are, scientists are actively working on making them even more so, both for better technology like navigation and geolocation and for scientific inquiries, like the basic nature of fundamental constants and gravity

The team endeavored to use a fundamentally quantum property—entanglement—to make pairs of atoms tick in tandem, thereby making the clock more precise. They cooled a gas of strontium atoms just above absolute zero and used optical tweezers to create a large array of atom pairs. These pairs were then made to interact using the same trick Schine had used during his graduate work: one atom absorbing a photon prevented another atom nearby from doing so as well, thus making their behavior depend on one another. Generating entangled atoms like this is a promising way to improve clock performance. They published this work in the journal Nature Physics

Now, Schine is starting to build up his own lab here at the University of Maryland. When deciding exactly what kind of experiment to embark upon, Schine was guided by his graduate school advisor Simon’s philosophy. “There are different strategies for setting up experiments,” Schine says. “But I think Jon’s was very much to build something that no one else has done before experimentally—to put ourselves in an area where there's a lot of low-hanging fruit.” Schine explained that this will involve combining his optical cavity expertise with an array of tweezer-trapped atoms, now using ytterbium. For instance, he predicts this will allow dramatic improvements in performing quantum measurements, which is an essential part of quantum computing or quantum simulation experiments. 

As Schine is assembling his lab and unique research program, he encourages interested students and postdocs to reach out to him. And, according to Schine’s undergraduate adviser, Schine’s teaching and mentoring abilities promise to be excellent. “One of the things we really work hard at in a place like Williams,” Majumder says, “is to make sure our students are not just the ones who can get into the lab, hide in a corner and just do amazing work. And that really comes through with Nathan. He's just such a good explainer of what he's doing. And he's so enthusiastic—it's very infectious.”

Story by Dina Genkina