Abstract: The study of quantum systems coupled to an environment plays a vital role in how we measure temperatures of the coldest and hottest matter in the universe. The strategy relies on introducing impurities into the system of interest and on observing how these probe particles evolve towards or in equilibrium with their surroundings, from which we may in turn deduce the thermal properties of that environment. Originally studied in the context of condensed matter physics, open quantum systems nowadays provide a common language to research spanning multiple orders of magnitude in temperature, ranging from Bose Einstein condensates made of ultracold atoms to the Quark-Gluon plasma created in ultra-relativistic collisions of heavy ions. This talk builds a bridge from polaron impurities in the former to quarkonium particles in the latter as two manifestations of quantum Brownian motion, a phenomenon ideally described by open quantum systems.

Time: 1:20pm~3:10pm, November 28 (Thursday)

Title: Probing entanglement dynamics on NISQ computers

Speaker: Associate Professor Hsiu-Chuan Hsu
(Graduate Institute of Applied Physics, National Chengchi University)

Place: Science Building III SC157

Abstract:

The quench dynamics of the Su-Schierffer-Heeger (SSH) chain is simulated on IBM Quantum computers. The second-order Rényi entanglement entropy, the twist order parameter and the Berry phase are calculated and shown persistent oscillations. Through error mitigation techniques, including global depolarizing error ansatz and postselection based on symmetry constraints, the simulation results match closely to the exact solution. Along with this research, a software tool is developed for effective simulation of entanglement entropy and a patent for monitoring quantum computers is granted.