Superfluidity and effective mass of magnetoexcitons in topological insulator bilayers: Effect of inter-Landau-level Coulomb interaction

TL;DR

This paper theoretically investigates how inter-Landau-level Coulomb interactions influence the effective mass and superfluid transition temperature of magnetoexcitons in topological insulator bilayers, revealing significant modifications to their properties.

Contribution

It introduces a more accurate numerical approach to account for inter-Landau-level Coulomb interactions, improving understanding of magnetoexciton behavior in topological insulator bilayers.

Findings

Inter-Landau-level Coulomb interactions significantly reduce magnetoexciton effective mass.

Inclusion of these interactions raises the superfluidity-normal phase transition temperature.

Numerical diagonalization provides more precise insights into magnetoexciton properties.

Abstract

The effective mass and superfluidity-normal phase transition temperature of magnetoexcitons in topological insulator bilayers are theoretically investigated. The intra-Landau-level Coulomb interaction is treated perturbatively, from which the effective magnetoexciton mass is analytically discussed. The inclusion of inter-Landau-level Coulomb interaction by more exact numerical diagonalization of the Hamiltonian brings out important modifications to magnetoexciton properties, which are specially characterized by prominent reduction in the magnetoexciton effective mass and promotion in the superfluidity-normal phase transition temperature at a wide range of external parameters.