Physics Colloquium: "Quantum Sensing With Gaussian and Non-Gaussian Light: From Fundamentals to Applications"

Please join the Department of Physics in welcoming Haocun Yu for her talk titled, "Quantum Sensing With Gaussian and Non-Gaussian Light: From Fundamentals to Applications."

Bio: Haocun Yu is an assistant professor working at the University of Tennessee working on quantum techniques and their various applications in quantum sensing, information and fundamental physics. Her research group focuses on creating novel quantum states, developing new quantum technologies and addressing fundamental questions about our world. Prior to joining UT, Haocun was a Marie-Curie Postdoctoral Fellow at the University of Vienna, where she conducted experiments on photon interferometry with entangled states to explore the interface between quantum mechanics and general relativity. She earned her Ph.D. in physics from MIT, where she worked in the Laser Interferometer Gravitational-Wave Observatory (LIGO) group on quantum techniques and phenomena in gravitational-wave detectors. Her work has been recognized with numerous honors, including the Boeing Quantum Creators Prize, MIT Technology Review’s Innovators Under 35, Rising Stars in Physics, the APS Carl E. Anderson Dissertation Award and the MIT Martin Deutsch Award.  

Abstract: Advanced quantum optical techniques are transforming quantum sensing, enabling unprecedented precision in how we observe and understand the universe. Two well-established catalogs of quantum optical states — squeezed states and single-photon states — are critical in this advancement. For squeezed light, I will discuss how squeezing has significantly enhanced the sensitivity of 4km gravitational-wave detectors, the largest quantum metrology experiment in the world. I will also explain the demonstration of quantum correlations in LIGO detectors, showcasing 40kg human-scale macroscopic quantum phenomena. For photon interferometry, I will describe how two-photon states sense Earth's rotation under a non-inertial frame, followed by the realization of a 50-km table-top fiber interferometer operating at the single-photon level, achieving a phase sensitivity in the order of 1E-16 rad RMS. This work also extends to potential applications in dark matter detection. Ultimately, all these achievements pave the way to create unprecedented quantum optical states, offering a novel platform not only for precision quantum measurements to address fundamental questions about our universe, but also for expanding the Hilbert space of quantum information processing.