As an undergraduate at the University of Illinois Urbana-Champaign, Haoran Lin found the perfect fit in physics. It combined both deep thinking and hands-on experiments—with outcomes that could chart the course for future technology.
During his senior year at the college, he met University of Chicago Pritzker School of Molecular Engineering (UChicago PME) Asst. Prof. Shuolang Yang. Yang visited the lab where Lin was conducting research as an undergraduate, and the two connected over their experiences with angle-resolved photoemission spectroscopy (ARPES), which is used to characterize thin materials.
“I liked what he was trying to do,” Lin said. “So I joined his lab as a PhD student directly from undergrad.”
Now, as a PhD student, Lin creates thin films of material using a technique called molecular beam epitaxy, then characterizes the material using ARPES. The goal is to create a topological superconductor from thin films of FeTeₓSe₁₋ₓ (iron-tellurium-selenium or FTS). Topological superconductors could potentially power future quantum computers, but first, scientists and engineers must find a way to grow and understand these materials.
While scientists have previously created bulk crystals of FTS, Lin is now growing two-dimensional thin films, which gives engineers more freedom to tune it for their needs. Once a thin film is grown, Lin characterizes it with the ARPES system to understand its electronic band structure. That gives him and his colleagues hints about the material’s topology and superconductivity.
“The goal is to establish this material as a thin film platform for topological superconductors, but there are very important questions we must answer about its structure first,” Lin said.
“We are literally stunned by the quality of the thin films created by Haoran, which enables a qualitatively different study of future topological quantum computing technologies,” said Yang. “Through days and nights of hardwork, Haoran is showing that the many-electron state behaves topologically different from the single-electron state, almost like how a school of fish moves differently from a single fish.”
The research requires not only a deep knowledge of physics, but also an engineer’s mind of the experimental setups. The systems are so sensitive that if a piece breaks, it could take months for Lin and others to fix it. “You have to be friends with the machines and know what’s going on,” Lin said. “It’s not like a microwave where you push start. We have lasers that require sensitive tuning and specific temperatures and humidities. I’ve gained a lot of hands-on experience fixing various parts of these machines.”
Outside of the lab, Lin enjoys exercising, whether running or biking by Lake Michigan. “Sometimes when I need to think about the equipment or materials, I go running,” he said. “It’s healthy, but it’s also good for my mental health.”
He also connects with his PME colleagues across departments. PhD students in materials science, for example, have helped teach him how to characterize his thin films. “UChicago PME enables collaborations you wouldn’t normally think of,” he said. “It’s really nice to be able to work with people from different backgrounds.”
Because he still has a couple years left before he finishes his PhD, Lin is still considering his career options—though his future will hopefully include more research in academia, ideally watching as his work helps transform technology. “We are close to claiming victory on these thin films soon,” he said. “I am excited to confirm topological superconductivity in these materials and show properties that have never been shown before.”
2025 International Year of Quantum Science and Technology
The United Nations declared 2025 the International Year of Quantum to mark a century of progress in quantum science and engineering. The University of Chicago and its partners join the celebration of the groundbreaking fields that continue to positively impact lives around the world.
