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arXiv · 2502.19228

Thermalization in a simple spin-chain model

Peter Reimann·Christian Eidecker-Dunkel
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Abstract

We consider the common spin-1/2 XX-model in one dimension with open boundary conditions and a large but finite number of spins. The system is in thermal equilibrium at times t<0, and is subject to a weak local perturbation (quantum quench) at t=0. Focusing mainly on single-spin perturbations and observables, we show that the system re-thermalizes for sufficiently large times t>0 without invoking any unproven assumptions besides the basic laws of quantum mechanics. Moreover, the time-dependent relaxation behavior is obtained in quantitative detail and is found to exhibit a wealth of interesting features.

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Peter Reimann, Christian Eidecker-Dunkel. 2025-02-26. Thermalization in a simple spin-chain model. https://doi.org/10.1103/physrevb.111.054312

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