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arXiv · 2304.03471

Quantum dynamics of non-Hermitian many-body Landau-Zener systems

Rajesh K. Malla·Julia Cen·Wilton J. M. Kort-Kamp·Avadh Saxena
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Abstract

We develop a framework to solve a large class of linearly driven non-Hermitian quantum systems. Such a class of models in the Hermitian scenario is commonly known as multi-state Landau-Zener models. The non-hermiticity is due to the anti-Hermitian couplings between the diabatic levels. We find that there exists a new conservation law, unique to this class of models, that describes the simultaneous growth of the unnormalized wavefunctions. These models have practical applications in Bose-Einstein condensates, and they can describe the dynamics of multi-species bosonic systems. The conservation law relates to a pair-production mechanism that explains the dissociation of diatomic molecules into atoms. We provide a general framework for both solvable and semiclassically solvable non-Hermitian Landau-Zener models. Our findings will open new avenues for a number of diverse emergent phenomena in explicitly time-dependent non-Hermitian quantum systems.

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Rajesh K. Malla, Julia Cen, Wilton J. M. Kort-Kamp, Avadh Saxena. 2023-04-07. Quantum dynamics of non-Hermitian many-body Landau-Zener systems. https://arxiv.org/abs/2304.03471

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