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arXiv · 2207.04682

Target space entanglement in quantum mechanics of fermions at finite temperature

Temma Hanyuda·Soichiro Mori·Sotaro Sugishita
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Abstract

We consider the target space entanglement in quantum mechanics of non-interacting fermions at finite temperature. Unlike pure states investigated in arXiv:2105.13726, the (R\'enyi) entanglement entropy for thermal states does not follow a simple bound because all states in the infinite-dimensional Hilbert space are involved. We investigate a general formula of the target space R\'enyi entropy for $N$ fermions at finite temperature, and present numerical results of the entropy in a one-dimensional model. We also argue the large $N$ behaviors with a comparison to the grand canonical ensemble.

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Temma Hanyuda, Soichiro Mori, Sotaro Sugishita. 2022-07-11. Target space entanglement in quantum mechanics of fermions at finite temperature. https://doi.org/10.1007/jhep09(2022)152

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