Caltech Alumnus Jin Ming Koh Wins LeRoy Apker Award From the American Physical Society

Each year the American Physical Society (APS) gives the LeRoy Apker Award to two individuals to provide "encouragement to students who have demonstrated great potential for future scientific accomplishment." This year, Jin Ming Koh (BS '23) has received the Apker Award "for the first experimental realization of a measurement-induced entanglement phase transition on a superconducting quantum processor." The award comes with a grant of $5,000 to the student, travel to an APS meeting to give an invited talk, and $5,000 to their undergraduate institution's physics department for support of undergraduate research.

Koh, who grew up in Singapore, chose Caltech for his undergraduate studies because he was searching for a tech university that was tight-knit and cohesive. "I came from a smaller high school that was STEM-focused, and I was looking for a similar college experience," Koh says. "Plus, Caltech is renowned for its rigor and its emphasis on research, even at the undergrad level, and that was attractive to me."

At Caltech in his second and third years, Koh worked in the lab of Austin Minnich, professor of mechanical engineering and applied physics, and division deputy chair for engineering and applied science. This research led to the publication of a paper in Nature Physics on how mid-circuit measurements on a superconducting quantum processor induced a phase transition in entanglement, a quantum phenomenon in which two particles link together in a certain way no matter how far apart they are in space. His findings showed that these mid-circuit measurements can cause qualitatively different behavior in the growth of entanglement in a quantum system, which can be studied to better understand aspects of quantum mechanics and quantum computation.

In his fourth year, Koh began collaborating with Jason Alicea, the William K. Davis Professor of Theoretical Physics, and co-mentor Etienne Lantagne-Hurtubise, Moore Postdoctoral Scholar Research Associate in Theoretical Physics, with whom he investigated the phases of matter realized by multiple layers of graphene, a structure that takes the form of a single layer of carbon atoms arranged in a honeycomb pattern. "Courtesy of an interplay of different mechanisms and electronic interactions," Koh says, "these materials exhibit exceptional tunability in their properties, ranging from insulating to superconducting phases."

Now at Harvard pursuing a PhD in physics, Koh anticipates continued research in quantum science. "I want to ask how we can effectively use the quantum technologies and processes that we have right now and in the future to learn more about physics and to do new things beyond our current classical ability," Koh explains.

"Truthfully, I was not aware that this award existed before I got nominated for it," Koh says. "I want to emphasize that even though I was the one given this award, it was an effort of all my co-authors, and I am especially grateful to the mentors that guided me throughout my undergraduate years, like Professor Austin Minnich and Professor Jason Alicea. My collaborator at IBM, Mario Motta, contributed so much and was an absolute pleasure to work with, and Shi-Ning Sun, then a graduate student in Professor Minnich's lab, introduced me to the group in the first place. I think it's important to recognize that this is not a one-person achievement."

"Koh's work is already stimulating further studies of the unique properties of quantum circuits with mid-circuit measurements," Minnich says. "The fact that he accomplished this feat as an undergraduate is simply astounding. I am so happy that he is receiving this well-deserved recognition." Alicea adds that "Jing Ming's productivity was amazing. He somehow managed to do pioneering research with Minnich's group while also breaking ground in very different areas of physics! It was a true joy witnessing his development at Caltech."