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arXiv · 1803.04634

Scattering of accelerated wave packets

S. Longhi·S. A. R. Horsley·G. Della Valle
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Abstract

Wave-packet scattering from a stationary potential is significantly modified when the wave-packet is subject to an external time-dependent force during the interaction. In the semiclassical limit, wave--packet motion is simply described by Newtonian equations and the external force can, for example, cancel the potential force making a potential barrier transparent. Here we consider wave-packet scattering from reflectionless potentials, where in general the potential becomes reflective when probed by an accelerated wave-packet. In the particular case of the recently-introduced class of complex Kramers-Kronig potentials we show that a broad class of time dependent forces can be applied without inducing any scattering, while there is a breakdown of the reflectionless property when there is a broadband distribution of initial particle momentum, involving both positive and negative components.

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S. Longhi, S. A. R. Horsley, G. Della Valle. 2018-03-13. Scattering of accelerated wave packets. https://doi.org/10.1103/physreva.97.032122

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