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arXiv · 2407.07746

Quantum Dynamics with Stochastic Non-Hermitian Hamiltonians

Pablo Martinez-Azcona·Aritra Kundu·Avadh Saxena·Adolfo del Campo·Aurelia Chenu
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Abstract

We study the quantum dynamics generated by a non-Hermitian Hamiltonian subject to stochastic perturbations in its anti-Hermitian part, describing fluctuating gains and losses. The dynamics averaged over the noise is described by an `anti-dephasing' master equation. We characterize the resulting state evolution and analyze its purity. The properties of such dynamics are illustrated in a stochastic dissipative qubit. Our analytical results show that adding noise allows for a rich control of the dynamics, stabilizing the lossy state and making state purification possible to a greater variety of steady states.

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Pablo Martinez-Azcona, Aritra Kundu, Avadh Saxena, Adolfo del Campo, Aurelia Chenu. 2024-07-10. Quantum Dynamics with Stochastic Non-Hermitian Hamiltonians. https://doi.org/10.1103/5ksl-tjjm

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