Fractional Quantum Hall Effect in Bilayer Two Dimensional Hole Gas Systems

TL;DR

This study explores the fractional and integer quantum Hall effects in high mobility bilayer 2D hole gases, revealing how interlayer interactions and imbalances influence quantum Hall states.

Contribution

It demonstrates the formation and evolution of bilayer quantum Hall states in hole gases with suppressed tunneling, highlighting their sensitivity to layer imbalance.

Findings

Bilayer $ u$=3/2 state is quickly destroyed by small imbalances.

Bilayer $ u$=1 state smoothly transitions into single layer $ u$=1.

Interlayer interactions are significant without tunneling interference.

Abstract

We have studied the fractional and integer quantum Hall effect in high mobility double layer 2D hole gas systems. The large hole effective mass inhibits tunneling, allowing us to investigate the regime in which the interlayer and intralayer interactions are comparable without significant interlayer tunneling occurring. As the interlayer separation is reduced we observe the formation of bilayer correlated quantum Hall states at total filling factor $\nu$=3/2 and $\nu$=1. We find that the bilayer $\nu$=3/2 state is rapidly destroyed by small carrier density imbalances between the layers, whereas the bilayer $\nu$=1 state evolves continuously into the single layer $\nu$=1 state.