Transport in T-shaped ballistic junction

TL;DR

This paper investigates ballistic transport in a three-terminal T-shaped junction, revealing how a floating electrode influences conductance, exhibits Wigner threshold effects, and enables current filtering, with analysis in both linear and non-linear regimes.

Contribution

It introduces a detailed study of ballistic transport in T-shaped junctions, highlighting the role of a floating electrode in conductance modulation and non-linear effects, which was not extensively explored before.

Findings

Conductance shows Wigner threshold effects and bend resistance.

The shape of Wigner singularities can be tuned by voltage and Fermi level shifts.

The system demonstrates filtering properties and back action effects in non-linear regime.

Abstract

We present studies of ballistic transport in three terminal T-shaped junction in a linear and non-linear regime. The floating electrode acts as a scatterer and modifies the conductance in a direct channel (between source and drain electrode). In the low voltage limit, the conductance shows the Wigner threshold effect and the bend resistance. A specific shape of the Wigner singularities can be changed by applied voltage to the floating electrode as well as by a shift of the Fermi level. The system also exhibits filtering properties with current distribution between different modes propagating in the junction. Back action of current flowing in the direct channel on changes of the voltage in the floating electrode is considered in the non-linear regime.