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arXiv · 2103.08132

Nonadiabaticity of Quantum harmonic oscillators

Hyeong-Chan Kim·Youngone Lee
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Abstract

We propose a quantity, ${\mathcal{A}\!\!\!/}$, as a measure describing the nonadiabaticity of a thermodynamic process. For this purpose, we use a schematic method to find the measure of the `degree of nonadiabaticity'. The method utilizes an `invariant' thermal state constructed from the Ermakov-Lewis-Riesenfeld invariant. Specifically, we study a frequency-modulated quantum harmonic oscillator as a thermodynamic system. Naturally, we write the first law of thermodynamics with ${\mathcal{A}\!\!\!/}$ as a measurable quantity. We discuss universality for the method and some possible applications.

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Hyeong-Chan Kim, Youngone Lee. 2021-03-15. Nonadiabaticity of Quantum harmonic oscillators. https://doi.org/10.1016/j.physleta.2022.127974

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