Quantum Research Institute Seminar | Nonequilibrium Quantum Dynamics on Quantum Simulators: From Ergodicity Breaking to Quantum Metrology

Abstract:
The development of quantum computers and simulators has opened new avenues for studying nonequilibrium quantum many-body dynamics through quantum simulation. In this talk, I will discuss how quantum simulation has deepened our understanding of quantum many-body chaos, thermalization, and their breakdown, with a focus on ergodicity breaking due to quantum many-body scar states. I will then discuss a recently proposed nonequilibrium quantum phase—strong-to-weak spontaneous symmetry breaking—uncovered through quantum simulations of open quantum systems. Finally, driven by the potential applications of weak ergodicity breaking and quantum simulators in quantum metrology, I will highlight our recent efforts to combat the noise in quantum metrology.

Bio:
Dr. Cheng-Ju Lin is an RQS (Robust Quantum Simulation) postdoctoral fellow at the University of Maryland. He received his Ph.D. in physics from Caltech and was a postdoctoral researcher at the Perimeter Institute before his current position. His research lies at the intersection of quantum information and condensed matter physics, focusing on quantum simulations of nonequilibrium dynamics—including quantum ergodicity, its breakdown, and nonequilibrium quantum phases—as well as their applications in quantum technology.