Berry Phase Oscillations of the Kondo Effect in Single-Molecule Magnets

Abstract

We show that it is possible to topologically induce or quench the Kondo resonance in the conductance of a single-molecule magnet (S>1/2) strongly coupled to metallic leads. This can be achieved by applying a magnetic field perpendicular to the molecule easy axis and works for both full- and half-integer spin cases. The effect is caused by the Berry phase interference between two quantum tunneling paths of the molecule's spin. We have calculated the renormalized Berry phase oscillations of the Kondo peaks as a function of the transverse magnetic field as well as the conductance of the molecule by means of the poor man's scaling method. We propose to use a new variety of the single-molecule magnet Ni4 for the experimental observation of this phenomenon.