Work

Quantum memory at an eigenstate phase transition in a weakly chaotic model

Year: 2022

Type: article

Abstract: We study a fully connected quantum spin model resonantly coupled to a small environment of noninteracting spins, and investigate how initial state properties are remembered at long times. We find memory of initial state properties, in addition to the total energy, that are not conserved by the dynamics. This memory occurs in the middle of the spectrum where an eigenstate quantum phase transition (ESQPT) occurs as a function of energy. The memory effect at that energy in the spectrum is robust to system-environment coupling until the coupling changes the energy of the ESQPT. This work demonstrates the effect of ESQPT memory as independent of integrability and suggests a wider generality of this mechanism for preventing thermalization at ESQPTs.

Source: Physical Review A

DOI: 10.1103/physreva.106.012206

Authors: M. R. Lambert, Shan-Wen Tsai, Shane P. Kelly

Institutions: University of California, Riverside, Los Alamos National Laboratory, University of California, Santa Barbara, Johannes Gutenberg University Mainz, Kavli Institute for Theoretical Physics

Language: English

Topic: Quantum chaos and dynamical systems

Subfield: Statistical and Nonlinear Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Science Foundation, Deutsche Forschungsgemeinschaft, Norges Idrettshøgskole

Awards: G1871477277, MRI: Acquisition of a Big Data Compute Cluster for Interdisciplinary Research, G7114732247, RAISE-TAQS: Nonlinear Optical Properties and Novel Quantum Phases of Polar Molecules in Optical Lattic, TRR 288: Elastisches Tuning und elastische Reaktion elektronischer Quantenphasen der Materie (ELASTOQMAT)