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Time scale of forerunners in quantum tunneling

G. Garcia-Calderon·Jorge Villavicencio·F. Delgado·J. G. Muga
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Abstract

The forerunners preceding the main tunneling signal of the wave created by a source with a sharp onset or by a quantum shutter, have been generally associated with over-the-barrier (non-tunneling) components. We demonstrate that, while this association is true for distances which are larger than the penetration lenght, for smaller distances the forerunner is dominated by under-the-barrier components. We find that its characteristic arrival time is inversely proportional to the difference between the barrier energy and the incidence energy, a tunneling time scale different from both the phase time and the Büttiker-Landauer (BL) time.

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G. Garcia-Calderon, Jorge Villavicencio, F. Delgado, J. G. Muga. 2002-06-04. Time scale of forerunners in quantum tunneling. https://doi.org/10.1103/physreva.66.042119

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