At small layer separations, the ground state of a nu=1 bilayer quantum Hall system exhibits spontaneous interlayer phase coherence and has a charged-excitation gap E_g. The evolution of this state with increasing layer separation d has been a matter of controversy. In this letter we report on small system exact diagonalization calculations which suggest that a single phase transition, likely of first order, separates coherent incompressible (E_g >0) states with strong interlayer correlations from incoherent compressible states with weak interlayer correlations. We find a dependence of the phase boundary on d and interlayer tunneling amplitude that is in very good agreement with recent experiments.
@article{arxiv.cond-mat/0006309,
title = {Strong Correlation to Weak Correlation Phase Transition in Bilayer Quantum Hall Systems},
author = {John Schliemann and S. M. Girvin and A. H. MacDonald},
journal= {arXiv preprint arXiv:cond-mat/0006309},
year = {2009}
}
Comments
4 pages, 4 figures included, version to appear in Phys. Rev. Lett