Influence of Correlated Hybridization on the Conductance of Molecular Transistors

TL;DR

This paper investigates how correlated hybridization affects conductance and spin polarization in molecular transistors, revealing nonuniversal behaviors and explaining experimental gate-voltage dependencies.

Contribution

It introduces the impact of occupancy-dependent hybridization in the Anderson impurity model, providing new insights into conductance deviations and spin polarization effects.

Findings

Correlated hybridization causes nonuniversal conductance deviations.

It modestly enhances spin polarization under magnetic fields.

Explains gate-voltage dependence of the Kondo scale observed experimentally.

Abstract

We study the spin-1/2 single-channel Anderson impurity model with correlated (occupancy dependent) hybridization for molecular transistors using the numerical renormalization-group method. Correlated hybridization can induce nonuniversal deviations in the normalized zero-bias conductance and, for some parameters, modestly enhance the spin polarization of currents in applied magnetic field. Correlated hybridization can also explain a gate-voltage dependence to the Kondo scale similar to what has been observed in recent experiments.