Observation of quantum thermalization restricted to Hilbert space fragments
Abstract
Quantum thermalization occurs in a broad class of systems from elementary particles to complex materials. Outofequilibrium quantum systems have long been understood to either thermalize or retain memory of their initial states, but not both. Here we achieve the first simultaneous demonstration of thermalization and memory in a quantum system. Using a Rydberg atom array, we observe quantum thermalization restricted to Hilbert space fragments, where the thermalized system retains characteristics of the initial configuration. Intriguingly, states from different subspaces do not thermalize with each other even when they have the same energy. Our work challenges established ideas of quantum thermalization while experimentally resolving the longstanding tension between thermalization and memory. These results may be applied to control entanglement dynamics in quantum processors and quantum sensors.
 Publication:

arXiv eprints
 Pub Date:
 March 2024
 DOI:
 10.48550/arXiv.2403.09517
 arXiv:
 arXiv:2403.09517
 Bibcode:
 2024arXiv240309517Z
 Keywords:

 Quantum Physics;
 Condensed Matter  Quantum Gases;
 Condensed Matter  Statistical Mechanics;
 Physics  Atomic Physics
 EPrint:
 13 pages, 11 figures