# Anti-$\mathcal{PT}$-symmetric Qubit: Decoherence and Entanglement Entropy

@article{Cen2020AntimathcalPTsymmetricQD, title={Anti-\$\mathcal\{PT\}\$-symmetric Qubit: Decoherence and Entanglement Entropy}, author={Julia Cen and Avadh B Saxena}, journal={arXiv: Quantum Physics}, year={2020} }

We investigate a two-level spin system based anti-parity-time (anti-$\mathcal{PT}$)-symmetric qubit and study its decoherence as well as entanglement entropy properties. We compare our findings with that of the corresponding $\mathcal{PT}$-symmetric and Hermitian qubits. First we consider the time-dependent Dyson map to find the exact analytical dynamics for a general non-Hermitian qubit system coupled with a bath, then we specialize it to the case of the anti-$\mathcal{PT}$-symmetric qubit. We…

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