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Barrier Perturbation Induced Superarrivals and Nonlocality in a Time-Evolving Wave Packet

Somshubhro Bandyopadhyay·Dipankar Home
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Abstract

We compute the time evolving probability of a Gaussian wave packet to be reflected from a rectangular potential barrier which is perturbed by reducing its height. A time interval is found during which this probability of reflection is enhanced (superarrivals) compared to the unperturbed case. Such a time evolving reflection probability implies that the effect of perturbation propagates across the wave packet faster than its group velocity - a curious form of nonlocality.

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Somshubhro Bandyopadhyay, Dipankar Home. 1999-07-08. Barrier Perturbation Induced Superarrivals and Nonlocality in a Time-Evolving Wave Packet. https://arxiv.org/abs/quant-ph/9907029

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