Critical tunneling currents in the regime of bilayer excitons

TL;DR

This paper studies tunneling in a bilayer quantum well system at half filling, revealing critical currents and near-zero interlayer voltage, indicating exciton Bose condensation.

Contribution

It provides experimental evidence of critical tunneling currents and near-zero interlayer voltage in a bilayer quantum well system, supporting exciton condensation.

Findings

Existence of critical tunneling currents

Near-zero interlayer voltage observed

Dependence of critical currents on condensate strength

Abstract

We have investigated the tunneling properties of an electron double quantum well system where the lowest Landau level of each quantum well is half filled. This system is expected to be a Bose condensate of excitons. Our four-terminal dc measurements reveal a nearly vanishing interlayer voltage and the existence of critical tunneling currents which depend on the strength of the condensate state.