Classical-to-stochastic Coulomb blockade cross-over in aluminum arsenide wires

TL;DR

This study investigates Coulomb blockade phenomena in aluminum arsenide quantum wires at very low temperatures, revealing a transition from classical to stochastic behavior and suggesting charge density wave conduction in a chain of quantum dots.

Contribution

It provides the first detailed analysis of the classical-to-stochastic Coulomb blockade crossover in aluminum arsenide quantum wires, including temperature-dependent resonance behavior.

Findings

Coulomb blockade resonances diminish below 250 mK

Evidence of a classical-to-stochastic crossover in quantum dots

Charge density wave conduction observed at high bias

Abstract

We report low-temperature differential conductance measurements in aluminum arsenide cleaved-edge overgrown quantum wires in the pinch-off regime. At zero source-drain bias we observe Coulomb blockade conductance resonances that become vanishingly small as the temperature is lowered below $250 {\rm mK}$. We show that this behavior can be interpreted as a classical-to-stochastic Coulomb blockade cross-over in a series of asymmetric quantum dots, and offer a quantitative analysis of the temperature-dependence of the resonances lineshape. The conductance behavior at large source-drain bias is suggestive of the charge density wave conduction expected for a chain of quantum dots.