The timemodulated barrier approach to traversal times from the Bohm trajectory point of view
Abstract
Büttiker and Landauer introduced the timemodulated barrier method for determining the average traversal time τ _{T} for an electron incident on a static barrier. This approach was motivated by the expectation that with the addition to the barrier of a small oscillatory component, V _{1}cosωt, the tunneling behaviour would exhibit distinct low (ω≪τ _{T}^{1}) and high (ω≫τ _{T}^{1}) frequency regimes. Recently De Raedt, García and Huyghebaert studied the scattering of gaussian wave packets by timemodulated rectangular barriers. They were unable to extract τ _{T} from the frequency dependence of the calculated transmission probability T(ω) ^{2}. In the present paper, possible reasons are suggested. In particular, it is argued that, at least within the Bohm trajectory interpretation of quantum mechanics, a very small increase in the transmission probability actually involves atypically long reflection times rather than the average transmission time of the unperturbed barrier. Hence, there is no reason to expect a signature of τ _{T} in T(ω) ^{2}. The Bohm trajectory approach is then used to investigated the ω dependence of the average traversal time and the distribution of traversal times both of which are found to exhibit interesting resonant behavior.
 Publication:

Solid State Communications
 Pub Date:
 June 1991
 DOI:
 10.1016/00381098(91)90121B
 Bibcode:
 1991SSCom..78.1015L