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arXiv · 2212.05512

Quantum irreversibility of quasistatic protocols for finite-size quantized systems

Yehoshua Winsten·Doron Cohen
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Abstract

Quantum mechanically, a driving process is expected to be reversible in the quasistatic limit, also known as the adiabatic theorem. This statement stands in opposition to classical mechanics, where a mix of regular and chaotic dynamics implies irreversibility. A paradigm for demonstrating the signatures of chaos in quantum irreversibility is a sweep process whose objective is to transfer condensed bosons from a source orbital. We show that such a protocol is dominated by an interplay of adiabatic-shuttling and chaos-assisted depletion processes. The latter is implied by interaction terms that spoil the Bogoliubov integrability of the Hamiltonian. As the sweep rate is lowered, a crossover to a regime that is dominated by quantum fluctuations is encountered, featuring a breakdown of quantum-to-classical correspondence. The major aspects of this picture are not captured by the common two-orbital approximation, which implies failure of the familiar many-body Landau-Zener paradigm.

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Yehoshua Winsten, Doron Cohen. 2023-05-07. Quantum irreversibility of quasistatic protocols for finite-size quantized systems. https://doi.org/10.1103/physreva.107.052202

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