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arXiv · 1808.06881

Density matrix of chaotic quantum systems

Xinxin Yang·Pei Wang
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Abstract

The nonequilibrium dynamics in chaotic quantum systems denies a fully understanding up to now, even if thermalization in the long-time asymptotic state has been explained by the eigenstate thermalization hypothesis which assumes a universal form of the observable matrix elements in the eigenbasis of Hamiltonian. It was recently proposed that the density matrix elements have also a universal form, which can be used to understand the nonequilibrium dynamics at the whole time scale, from the transient regime to the long-time steady limit. In this paper, we numerically test these assumptions for density matrix in the models of spins.

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Xinxin Yang, Pei Wang. 2020-12-07. Density matrix of chaotic quantum systems. https://doi.org/10.1140/epjb%2Fe2020-10074-9

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