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arXiv · 1407.6136

Thermal states of random quantum many-body systems

Yoshifumi Nakata·Tobias J. Osborne
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Abstract

We study a distribution of thermal states given by random Hamiltonians with a local structure. We show that the ensemble of thermal states monotonically approaches the unitarily invariant ensemble with decreasing temperature if all particles interact according to a single random interaction and achieves a state $t$-design at temperature $O(1/\log(t))$. For the system where the random interactions are local, we show that the ensemble achieves a state $1$-design. We then provide numerical evidence indicating that the ensemble undergoes a phase transition at finite temperature.

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Yoshifumi Nakata, Tobias J. Osborne. 2014-11-26. Thermal states of random quantum many-body systems. https://doi.org/10.1103/physreva.90.050304

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