A comparative analysis of tunneling time concepts: Where do transmitted particles start from, on the average?

Abstract

In this paper we compare the concept of the tunneling time introduced in quant-ph/0405028 with those of the phase and dwell times. As is shown, unlike the latter our definition of the transmission time coincides, in the limit of weak scattering potentials, with that for a free particle. This is valid for all values of the particle's momentum, including the case of however slow particles. All three times are also considered for a resonant tunneling. In all the cases the main feature to distinguish our concept from others is that the average starting point of transmitted (reflected) particles does not coincide with that of all particles. One has to stress here that there is no such an experiment which would give coordinates of all the three points, simultaneously. For measuring the position of the average starting point of transmitted particles we propose an experimental scheme based on the Larmor precession effect.