Abstract: Periodically driven many-body systems generally heat towards a featureless "infinite-temperature" state. As an alternative to uniform heating in a clean system, here we establish a Floquet superheating regime, where fast heating nucleates at "hot spots" generated by rare fluctuations in the local energy with respect to an appropriate effective Hamiltonian. Striking macroscopic consequences include exceptionally long-lived prethermalization and non-ergodic bimodal distributions of macroscopic observables. Superheating is predicated on a heating rate depending strongly on the local fluctuation; in our example, this is supplied by a sharp state-selective spin-echo, where the energy absorption is strongly suppressed for low-energy states, while thermal fluctuations open up excessive heating channels. A simple phenomenological theory is developed to show the existence of a critical droplet size, which incorporates heating by the driving field as well as the heat current out of the droplet. Our results shine light on a new heating mechanism and suggest new routes towards stabilizing non-equilibrium phases of matter in driven systems.

Reference: arXiv:2511.12877

About the speaker: Dr. Hongzheng Zhao is an Assistant Professor at Peking University. He received his bachelor's degree from Shandong University in 2017 and his Ph.D. from Imperial College London in 2021. After a postdoctoral position at the Max Planck Institute for the Physics of Complex Systems, he joined Peking University in 2023. His research focuses on nonequilibrium many-body dynamics, including quantum thermalization, driven systems, strongly correlated systems, quantum simulation, and quantum computation.

Inviter: 孙孝奇 xqsun@iphy.ac.cn