Influence of zero-point anomalies in the electron density of states of electrodes on the inelastic tunneling spectrum

It is shown that a minimum in the electron density of states near the Fermi surface of one of the electrodes shifts the peaks in inelastic tunneling spectrum toward higher voltages. The shift depends on the correlation parameter and increases with temperature. It is argued that the observation of the shift in the local singularities of inelastic tunneling, in conjunction with the presence of large-scale zero-point anomaly in the differential conductivity, can serve as a firm evidence of the presence of the corresponding singularity in the electron density of metal oxides and magnetoresistive materials.