Ground State of v=1 Bilayer Quantum Hall Systems

TL;DR

This paper investigates the evolution of the ground state in v=1 bilayer quantum Hall systems as layer separation increases, revealing a smooth crossover from excitonic to Fermi-liquid behavior through DMRG calculations.

Contribution

It provides a detailed analysis of the ground state transition in bilayer quantum Hall systems using DMRG, highlighting the continuous nature of the crossover.

Findings

Smooth crossover from excitonic to Fermi-liquid state at d/l ~ 1.6

Ground state transition is continuous

Calculated energy gap and distribution functions support the crossover

Abstract

The ground-state wave function and the energy gap are calculated for various layer separations d and for up to 24 electrons by the density matrix renormalization group (DMRG) method. Two-particle distribution function and excitonic correlation function are calculated from the ground-state wave function, and the evolution of the ground state with increasing d is analyzed. The results indicate that the transition is continuous. A smooth crossover of the ground state is found at around d/l ~ 1.6 from the excitonic character at small d/l to the independent Fermi-liquid character at large d/l, where l is the magnetic length.