Effect of Interactions on the Admittance of Ballistic Wires

TL;DR

This paper develops a self-consistent theory for the admittance of ballistic wires, showing how interactions and screening effects alter frequency responses and induce resonant behaviors in multi-channel systems.

Contribution

It introduces a novel self-consistent model that accounts for interactions and screening, revealing new frequency-dependent features in ballistic wire admittance.

Findings

Screening effects significantly alter conductance frequency behavior.

Multi-channel systems exhibit resonant structures in admittance.

Imaginary part of admittance can become negative near resonances.

Abstract

A self-consistent theory of the admittance of a perfect ballistic, locally charge neutral wire is proposed. Compared to a non-interacting theory, screening effects drastically change the frequency behavior of the conductance. In the single-channel case the frequency dependence of the admittance is monotonic, while for two or more channels collective interchannel excitations lead to resonant structures in the admittance. The imaginary part of the admittance is typically positive, but can become negative near resonances.