PERTURBATION OF TUNNELING PROCESSES BY MECHANICAL DEGREES OF FREEDOM IN MESOSCOPIC JUNCTIONS

We investigate the perturbation in the tunneling current caused by non adiabatic mechanical motion in a mesoscopic tunnel junction. A theory introduced by Caroli et al. is used to evaluate second-order self-ener gy corrections for this nonequilibrium situation lacking translational invariance. Inelastic signatures of the mechanical degrees of freedom are found in the current-voltage I(V) characteristics. These give ris e to sharp features in the derivative spectrum, d(2)I/dV(2).