Rippled state of double-layer quantum Hall systems

TL;DR

This paper predicts a rippled dipole charge density in unbalanced bilayer quantum Hall systems, which can be experimentally detected and is associated with a tunable density-wave instability.

Contribution

It introduces the concept of a rippled dipole density in the incommensurate phase of bilayer quantum Hall states and demonstrates this through Hartree-Fock calculations.

Findings

Identification of rippled dipole charge density in unbalanced bilayer systems

Prediction of a tunable density-wave instability

Potential detection via capacitance and transport measurements

Abstract

The incommensurate phase of a bilayer quantum Hall state is found to have a ``rippled'' dipole charge density whenever the layers are unbalanced. This tunable dipole-density-wave instability could be detected by sensitive capacitance measurements and by anisotropic transport. We demonstrate this explicitly by carrying out a Hartree-Fock calculation of the layer densities and capacitance for a double-layer quantum Hall state at a total filling factor of 1.