Physica Scripta
Tunneling with coupling to surface phonons or surface plasmons
A. Tagliacozzo, Erio Tosatti
Abstract
Results are here reported of a model calculation for the one-dimensional tunneling of a particle coupled to a quantum harmonic oscillator. Interaction is at the barrier, to mimick the influence on transmission of possible surface excitations. The tunneling process turns out to be fast with respect to low energy modes such as surface phonons. Total transmission is enhanced with respect to the case without coupling, while the elastic one shows a kind of dissipative behaviour. On the contrary, the time scale for resonant tunneling is ?, where ? is the halfwidth of the resonance. Virtual excitation of high energy modes (e.g., surface plasmons) acts as a van der Waals-type force which renormalizes the barrier and increases the elastic transmission.