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arXiv · 2512.03935

Thermodynamics of an Open Two-Level $\mathcal{PT-}$Symmetric Quantum System

Baibhab Bose·Devvrat Tiwari·Subhashish Banerjee
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Abstract

For a subclass of a general $\mathcal{PT}-$symmetric Hamiltonian obeying anti-commutation relation with its conjugate, a Hermitian basis is found that spans the bi-orthonormal energy eigenvectors. Using the modified projectors constructed from these eigenvectors, the generalized density matrix of the $\mathcal{PT}-$symmetric evolution is calculated, and subsequently, ergotropy for a closed system is obtained. The $\mathcal{PT}-$symmetric system, in an open system scenario, is studied to understand ergotropy under different regimes of non-Hermiticity of the Hamiltonian. The consistency of the three laws of thermodynamics for the $\mathcal{PT}-$symmetric system in an open system scenario is also analyzed.

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Baibhab Bose, Devvrat Tiwari, Subhashish Banerjee. 2025-12-03. Thermodynamics of an Open Two-Level $\mathcal{PT-}$Symmetric Quantum System. https://doi.org/10.1088/1751-8121%2Fae98c7

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