Talk page
Title:
From short-time to late-time dynamics: many-particle interference in interacting bosonic systems
Speaker:
Abstract:
Concepts based on many-particle interference have proven very fruitful for better understanding various many-body phenomena, such as quantum dynamics of cold atoms, many-body localization and more recently information scrambling. We will address such phenomena by using semiclassical path integral techniques based on interfering Feynman paths, bridging classical and quantum many-body approaches. On the one hand we use short-time dynamical information to compute many-body level densities. We show that the crossover from an ideal Bose gas to the strongly correlated, fermionized gas, exhibits universal behavior: Systems with very few up to many particles share the same underlying spectral features. On the other hand, corresponding semiclassical techniques for large-N Bose-Hubbard systems, which are based on coherent sums over solutions of the corresponding mean-field equations, enable us to account for quantum entanglement at intermediate to post-Ehrenfest (scrambling) time scales where classical and quantum evolution diverges: We compute out-of-time-order correlators (OTOCs) and discuss the quantum mechanisms leading to their saturation for quantum chaotic and to quasi-periodic recurrences of OTOCs for quantum critical many-body systems.
Link:
Workshop: