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arXiv · 1907.11088

Controlling decoherence via $\mathcal{PT}$-symmetric non-Hermitian open quantum systems

Sanjib Dey·Aswathy Raj·Sandeep K. Goyal
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Abstract

We have studied the effect of a non-Hermitian Bosonic bath on the dynamics of a two-level spin system. The non-Hermitian Hamiltonian of the bath is chosen such that it converges to the harmonic oscillator Hamiltonian when the non-Hermiticity is switched off. We calculate the dynamics of the spin system and found that the non-Hermiticity can have positive as well as negative effects on the coherence of the system. However, the decoherence can be completely eliminated by choosing the non-Hermiticity parameter and the phase of the system bath interaction appropriately. We have also studied the effect of this bath on the entanglement of a two-spin system when the bath is acting only on one spin.

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Sanjib Dey, Aswathy Raj, Sandeep K. Goyal. 2019-07-23. Controlling decoherence via $\mathcal{PT}$-symmetric non-Hermitian open quantum systems. https://doi.org/10.1016/j.physleta.2019.125931

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