Abstract: Drawing inspiration from gravity and solvable SYK-type models, recent developments in the study ofinformation scrambling have identified the scramblon, a novel collective excitation in quantum many-body systems with all-to-all connectivity, as the fundamental carrier of scrambling dynamics. In this talk, I will present our recent collaboration withthe experimental group at USTC, demonstrating the validity of scramblon theory in a solid-state NMR system. Crucially, thisenables us to isolate and mitigate errors in the OTOC caused by imperfections in the backward evolution, which uncovers theanticipated exponential behavior of quantum many-body chaos and extracts the quantum Lyapunov exponent in a many-bodyexperimental system for the first time. I will also present our further theoretical proposal for distinguishing coherent andincoherent errors using multi-round time-reversed dynamics.

Bio: Pengfei Zhang is an associate professor in the Department of Physics at Fudan University in Shanghai, China. He received his BSc andPhD in plysics from Tsinghua University in China and conducted postdoctoral research at Caltech. He has broad interests in the dynamics ofquantum many-body systems. His recent research has focused on topics such as quantum information in solvable models, driven and monitored quantum systems, and quantum thermalization