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Coherent states for time dependent harmonic oscillator: the step function

H. Moya-Cessa·M. Fernandez-Guasti
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Abstract

We study the time evolution for the quantum harmonic oscillator subjected to a sudden change of frequency. It is based on an approximate analytic solution to the time dependent Ermakov equation for a step function. This approach allows for a continuous treatment that differs from former studies that involve the matching of two time independent solutions at the time when the step occurs.

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H. Moya-Cessa, M. Fernandez-Guasti. 2003-01-21. Coherent states for time dependent harmonic oscillator: the step function. https://doi.org/10.1016/s0375-9601(03)00461-4

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