Arresting Quantum Chaos Dynamically in Transmon Arrays

Autor: Mukherjee, Rohit, Guo, Haoyu, Lewellen, Keiran, Chowdhury, Debanjan
Rok vydání: 2024
Předmět:
Druh dokumentu: Working Paper
Popis: Ergodic quantum many-body systems evolving under unitary time dynamics typically lose memory of their initial state via information scrambling. Here we consider a paradigmatic translationally invariant many-body Hamiltonian of interacting bosons -- a Josephson junction array in the transmon regime -- in the presence of a strong Floquet drive. Generically, such a time-dependent drive is expected to heat the system to an effectively infinite temperature, featureless state in the late-time limit. However, using numerical exact-diagonalization we find evidence of special ratios of the drive amplitude and frequency where the system develops {\it emergent} conservation laws, and {\it approximate} integrability. Remarkably, at these same set of points, the Lyapunov exponent associated with the semi-classical dynamics for the coupled many-body equations of motion drops by orders of magnitude, arresting the growth of chaos. We supplement our numerical results with an analytical Floquet-Magnus expansion that includes higher-order corrections, and capture the slow dynamics that controls decay away from exact freezing.
Comment: 14 pages, 14 figures
Databáze: arXiv