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arXiv · 2303.01881

Some speculations about local thermalization of nonequilibrium extended quantum systems

M. Coppola·D. Karevski
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Abstract

We discuss the possibility of defining an emergent local temperature in extended quantum many-body systems evolving out of equilibrium. For the most simple case of free-fermionic systems, we give an explicit formula for the effective temperature in the case of, not necessarily unitary, Gaussian preserving dynamics. In this framework, we consider the hopping fermions on a one-dimensional lattice submitted to randomly distributed projective measurements of the local occupation numbers. We show from the average over many quantum trajectories that the effective temperature relaxes exponentially towards infinity.

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M. Coppola, D. Karevski. 2023-03-03. Some speculations about local thermalization of nonequilibrium extended quantum systems. https://doi.org/10.5488/cmp.26.13502

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