Interlayer tunneling in counterflow experiments on the excitonic condensate in quantum Hall bilayers

TL;DR

This study investigates how tunneling affects transport in quantum Hall bilayers with excitonic condensates, revealing a critical current where tunneling behavior shifts and impacts resistance.

Contribution

It demonstrates the existence of a critical tunneling current that separates regimes of strong and negligible tunneling in quantum Hall bilayers.

Findings

Tunneling is significant below a critical current $I_C$.

Above $I_C$, tunneling becomes negligible.

Layer resistance increases rapidly beyond $I_C$.

Abstract

The effect of tunneling on the transport properties of} quantum Hall double layers in the regime of the excitonic condensate at total filling factor one is studied in counterflow experiments. If the tunnel current $I$ is smaller than a critical $I_C$, tunneling is large and is effectively shorting the two layers. For $I > I_C$ tunneling becomes negligible. Surprisingly, the transition between the two tunneling regimes has only a minor impact on the features of the filling-factor one state as observed in magneto-transport, but at currents exceeding $I_C$ the resistance along the layers increases rapidly.