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Complex--Barrier Tunnelling Times

Fabio Raciti·Giovanni Salesi
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Abstract

In this paper we calculate the analytic expression of the phase time for the scattering of an electron off a complex square barrier. As is well known the (negative) imaginary part of the potential takes into account, phenomenologically, the absorption. We investigate the so-called Hartman-Fletcher effect, and find that it is suppressed by the presence of a (not negligible) imaginary potential. In fact, when a sufficiently large absorption is present, the asymptotical transmission speed is finite. Actually, the tunnelling time does increase linearly with the barrier width. A recent optical experiment seems to be in agreement with our theoretical previsions.

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Fabio Raciti, Giovanni Salesi. 2002-03-19. Complex--Barrier Tunnelling Times. https://doi.org/10.1051/jp1:1994220

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