Power-law behavior in electron transport through a quantum dot with Luttinger liquid leads

Abstract

The electron transport of a system consisting of a Kondo dot and two Luttinger liquid (LL) leads is theoretically studied by use of nonequilibrium Green function approach. In the Kondo regime, the zero bias anomaly appears and the density of states of the dot obeys a power-law scaling at positive energy part with an exponent β/2 = 1/g − 1, where g reflects the electron interaction in the LL leads. The differential conductance shows a power-law scaling both in bias voltage and in temperature, with the exponent being β. The power-law temperature dependence of the peak conductance is observed in different temperature regimes. These features are ascribed to the LL correlation in the leads. Our work describes both the zero bias anomaly and power-law scalings within one theoretical frame.