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arXiv · 1906.08840

Time-independent approximations for time-dependent optical potentials

Andreas Fring·Rebecca Tenney
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Abstract

We explore the possibility of modifying the Lewis-Riesenfeld method of invariants developed originally to find exact solutions for time-dependent quantum mechanical systems for the situation in which an exact invariant can be constructed, but the subsequently resulting time-independent eigenvalue system is not solvable exactly. We propose to carry out this step in an approximate fashion, such as employing standard time-independent perturbation theory or the WKB approximation, and subsequently feeding the resulting approximated expressions back into the time-dependent scheme. We illustrate the quality of this approach by contrasting an exactly solvable solution to one obtained with a perturbatively carried out second step for two types of explicitly time-dependent optical potentials.

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Andreas Fring, Rebecca Tenney. 2019-10-16. Time-independent approximations for time-dependent optical potentials. https://doi.org/10.1140/epjp%2Fs13360-020-00143-y

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