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arXiv · 2503.17723

Thermal properties of a non-Hermitian system interacting with oscillator

Gargi Das·Bhabani Prasad Mandal
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Abstract

In this work, we consider a two level $P\sigma_{z}$ pseudo-Hermitian system in contact with a thermal bath to study various thermodynamic properties. The system is realized in terms of infinitely many invariant subspaces. We find explicit solution in each subspace analytically. The quantum system undergoes a $P\sigma_{z}$ phase transition in each invariant subspace, when the non-Hermitian coupling exceeds a certain critical value ($\mu_c$). We calculate various thermodynamic quantities and observe that these quantities show divergences exactly at the exceptional points (EPs) of the theory.

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Gargi Das, Bhabani Prasad Mandal. 2025-03-22. Thermal properties of a non-Hermitian system interacting with oscillator. https://arxiv.org/abs/2503.17723

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