Dephasing in semiconductor-superconductor structures by coupling to a voltage probe

TL;DR

This paper investigates how coupling to a voltage probe causes dephasing in semiconductor-superconductor structures, analyzing conductance behavior in a double-barrier junction and the suppression of conductance enhancement at resonance.

Contribution

It introduces a model for dephasing via a voltage probe in semiconductor-superconductor systems, focusing on the effects in a double-barrier junction with variable transparency.

Findings

Dephasing reduces conductance enhancement at resonance.

Conductance depends on Fermi level position and barrier transparency.

Finite coupling to the voltage probe suppresses ideal conductance doubling.

Abstract

We study dephasing in semiconductor-superconductor structures caused by coupling to a voltage probe. We consider structures where the semiconductor consists of two scattering regions between which partial dephasing is possible. As a particular example we consider a situation with a double-barrier junction in the normal region. For a single-mode system we study the conductance both as a function of the position of the Fermi level and as a function of the barrier transparency. At resonance, where the double-barrier is fully transparent, we study the suppression of the ideal factor-of-two enhancement of the conductance when a finite coupling to the voltage probe is taken into account.