Coulomb Blockade with Dispersive Interfaces

TL;DR

This paper investigates how frequency-dependent conductance at the interface influences Coulomb blockade oscillations, emphasizing the role of ac dissipative conductance and interface-induced capacitance or inductance.

Contribution

It introduces a framework linking Coulomb blockade oscillations to ac dissipative conductance and interface effects, supported by both perturbative and non-perturbative analyses.

Findings

Coulomb blockade oscillations are controlled by ac dissipative conductance.

Interface-induced capacitance or inductance significantly alters the effective charging energy.

Theoretical models are validated through examples in weak and strong coupling regimes.

Abstract

What quantity controls the Coulomb blockade oscillations if the dot--lead conductance is essentially frequency--dependent ? We argue that it is the ac dissipative conductance at the frequency given by the effective charging energy. The latter may be very different from the bare charging energy due to the interface--induced capacitance (or inductance). These observations are supported by a number of examples, considered from the weak and strong coupling (perturbation theory vs. instanton calculus) perspectives.