Southwest Quantum Information and Technology

Quantum simulation of many-body non-equilibrium dynamics in tilted 1D Fermi-Hubbard models

Presenting Author: Bharath Hebbe Madhusudhana, Max-Planck-Institute for Quantum Optics
Contributing Author(s): Sebastian Scherg, Thomas Kohlert, Pablo Sala, Frank Pollmann, Immanuel Bloch, Monika Aidelsburger

Thermalization of isolated quantum many-body systems is a redistribution of quantum information within the system in such a way that macroscopic variables remain experimentally accessible and microscopic variables recede into inaccessible parts of the Hilbert space. Therefore, a question of fundamental importance to quantum information theory is when do quantum many-body systems fail to thermalize, i.e., feature non-ergodicity. A useful test-bed for the study of non-ergodicity is the tilted Fermi-Hubbard model, which is directly accessible in experiments with ultracold atoms in optical lattices. Here we experimentally study non-ergodic behavior in this model by tracking the evolution of an initial charge-density wave over a wide range of parameters, where we find a remarkably long-lived initial-state memory [1]. In the limit of large tilts, we identify the microscopic processes which the observed dynamics arise from. These processes constitute an effective Hamiltonian and we experimentally show its validity [2]. This effective Hamiltonian features the novel phenomenon of Hilbert space fragmentation. In the intermediate tilt regime, while these effective models are no longer valid, we show that the features of fragmentation are still vaguely present in the dynamics. Finally, we explore the relaxation dynamics of the imbalance in a 2D tilted Fermi-Hubbard system. [1.] Sebastian Scherg et al. arXiv:2010.12965 [2.] Thomas Kohlert et al. arXiv:2106.15586

Read this article online: https://arxiv.org/abs/2010.12965, https://arxiv.org/abs/2106.15586

(Session 5 : Thursday from 12:00pm-2:00pm)