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Quantum dwell times

J. A. Damborenea·I. L. Egusquiza·J. G. Muga·B. Navarro
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Abstract

We put forward several inherently quantum characteristics of the dwell time, and propose an operational method to detect them. The quantum dwell time is pointed out to be a conserved quantity, totally bypassing Pauli's theorem. Furthermore, the quantum dwell time in a region for one dimensional motion is doubly degenerate. In presence of a potential barrier, the dwell time becomes bounded, unlike the classical quantity. By using off-resonance coupling to a laser we propose an operational method to measure the absorption by a complex potential, and thereby the average time spent by an incoming atom in the laser region.

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J. A. Damborenea, I. L. Egusquiza, J. G. Muga, B. Navarro. 2004-03-10. Quantum dwell times. https://arxiv.org/abs/quant-ph/0403081

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