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arXiv · 2204.07595

Long-range Kitaev chain in a thermal bath: Analytic techniques for time-dependent systems and environments

Emma C. King·Michael Kastner·Johannes N. Kriel
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Abstract

We construct and solve a "minimal model" with which nonequilibrium phenomena in many-body open quantum systems can be studied analytically under time-dependent parameter changes in the system and/or the bath. Coupling a suitable configuration of baths to a Kitaev chain, we self-consistently derive a Lindblad master equation which, at least in the absence of explicit time dependencies, leads to thermalization. Using the method of Third Quantization we derive time-evolution equations for the correlation matrix, which we relate to the occupation of the system's quasiparticle modes. These results permit analytic and efficient numeric descriptions of the nonequilibrium dynamics of open Kitaev chains under a wide range of driving protocols, which in turn facilitate the investigation of the interplay between bath-induced dissipation and the generation of coherent excitations by nonadiabatic driving. We advertise this minimal model of maximum simplicity for the study of finite-temperature generalizations of Kibble-Zurek ramps, Floquet physics, and many other nonequilibrium protocols of quantum many-body systems driven by time-varying parameters and/or temperatures.

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Emma C. King, Michael Kastner, Johannes N. Kriel. 2022-04-15. Long-range Kitaev chain in a thermal bath: Analytic techniques for time-dependent systems and environments. https://doi.org/10.1140/epjs/s11734-025-01788-5

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