Mesoscopic Charge Relaxation

TL;DR

This paper investigates charge relaxation in mesoscopic RC circuits, demonstrating universal resistance behavior under various conditions and comparing theoretical predictions with experimental data.

Contribution

It introduces a self-consistent scattering theory and Hartree-Fock analysis showing universality of charge relaxation resistance even with Coulomb blockade effects.

Findings

Charge relaxation resistance is universal and equals half a resistance quantum.

Universality holds at zero temperature even with Coulomb blockade.

Temperature and magnetic field cause deviations from universality.

Abstract

We consider charge relaxation in the mesoscopic equivalent of an RC circuit. For a single-channel, spin-polarized contact, self-consistent scattering theory predicts a universal charge relaxation resistance equal to half a resistance quantum independent of the transmission properties of the contact. This prediction is in good agreement with recent experimental results. We use a tunneling Hamiltonian formalism and show in Hartree-Fock approximation, that at zero temperature the charge relaxation resistance is universal even in the presence of Coulomb blockade effects. We explore departures from universality as a function of temperature and magnetic field.