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arXiv · 2505.16545

$\mathcal{PT-}$Symmetric Two-Level Open Quantum Systems: Information Theoretic Facets

Baibhab Bose·Devvrat Tiwari·Subhashish Banerjee
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Abstract

The theory of a two-level $\eta$-Hermitian Hamiltonian with $\mathcal{PT}$ symmetry is reviewed and extended to include open system dynamics. A first-principles derivation of the generalized Gorini-Kossakowski-Sudarshan-Lindblad master equation appropriate for a $\mathcal{PT}-$symmetric Hamiltonian is presented. Inspired by a simple light matter interaction open system model, information theoretic quantities like a non-Markovian witness and fidelity are calculated for the $\mathcal{PT-}$symmetric Hamiltonian, and the results are compared with their corresponding two-level Hermitian counterparts. The nature of entanglement between two $\mathcal{PT-}$symmetric and Hermitian open quantum systems is calculated, and the contrast observed.

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Baibhab Bose, Devvrat Tiwari, Subhashish Banerjee. 2025-05-22. $\mathcal{PT-}$Symmetric Two-Level Open Quantum Systems: Information Theoretic Facets. https://doi.org/10.1088/1402-4896%2Fae64ba

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