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arXiv:2610.16788

Information Entropy as a Sensitive Diagnostic of Relaxation Dynamics in a Quasiperiodic Mott Insulator

N. D. Chavda, A. M. S. Macêdo, Robin P. Sagar, Barnali Chakrabarti

Published Oct 12, 2026• 0 citations
arXivHTMLPDF

Abstract

We study the nonequilibrium dynamics of a bosonic Mott insulator following a sudden quench from a periodic to a quasiperiodic lattice. Using ab initio multiconfigurational (MCTDHB) continuum many-body dynamics, we characterize the evolution through momentum distributions, fragmenta- tion, correlation functions, and information entropy. We find that melting of Mott correlations does not necessarily imply relaxation of the many-body state. In the weakly interacting regime, the initial Mott-like correlation undergo recurrent melting and partial recovery, while the information entropy displays large, intermittent fluctuations within the simulated time window. In contrast, a strongly interacting and fully fragmented Mott insulator retains its characteristic Mott correla- tions, up to partial distortions, while the many-body information entropy approaches a well-defined stationary regime plateau with comparatively small fluctuations. These results indicate that Mott- correlation dynamics and many-body relaxation can be dissociated in this finite system and support the use of information entropy, evaluated in the multiconfigurational representation, as a sensitive complementary diagnostic of nonequilibrium relaxation.

DOI
10.48550/arxiv.2610.16788

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