Solitonic Excitations in Linearly Coherent Channels of Bilayer Quantum Hall Stripes

TL;DR

This paper investigates solitonic excitations in bilayer quantum Hall stripe phases, calculating the transport gap via a microscopic Hartree-Fock approach and comparing it with field-theoretic estimates, revealing lower excitation energies for solitons.

Contribution

It provides a detailed microscopic calculation of the transport gap due to solitons in bilayer quantum Hall stripe phases, extending understanding of their excitations.

Findings

Soliton-antisoliton excitation energy is lower than electron-hole pair energy.

Transport gap depends on interlayer distance and tunneling amplitude.

Microscopic Hartree-Fock results align with field-theoretic estimates.

Abstract

In some range of interlayer distances, the ground state of the two-dimensional electron gas at filling factor nu =4N+1 with N=0,1,2,... is a coherent stripe phase in the Hartree-Fock approximation. This phase has one-dimensional coherent channels that support charged excitations in the form of pseudospin solitons. In this work, we compute the transport gap of the coherent striped phase due to the creation of soliton-antisoliton pairs using a supercell microscopic unrestricted Hartree-Fock approach. We study this gap as a function of interlayer distance and tunneling amplitude. Our calculations confirm that the soliton-antisoliton excitation energy is lower than the corresponding Hartree-Fock electron-hole pair energy. We compare our results with estimates of the transport gap obtained from a field-theoretic model valid in the limit of slowly varying pseudospin textures.