KONDO RESONANCE IN TUNNELING PHENOMENA THROUGH A SINGLE QUANTUM LEVEL

Effects of Coulomb repulsion on the process of resonant tunneling through a single quantum level are studied by applying the quantum Monte Carlo method and the maximum-entropy method to the Wolf model on a one-dimensional chain. In the calculated spectral function there is a sharp Kondo peak near the chemical potential μ, which contributes to the resonance tunneling. Correspondingly, the conductance calculated by using the Friedel sum rule shows the expected transparency, i.e., the transmission probability is almost unity when μ is in the range ε0<μ<ε0+U, where ε0 is the on-site energy of the single quantum level and U is the Coulomb repulsion. © 1995 The American Physical Society.