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Strong Correlation to Weak Correlation Phase Transition in Bilayer Quantum Hall Systems

John Schliemann·S. M. Girvin·A. H. MacDonald
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Abstract

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.

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John Schliemann, S. M. Girvin, A. H. MacDonald. 2001-01-03. Strong Correlation to Weak Correlation Phase Transition in Bilayer Quantum Hall Systems. https://doi.org/10.1103/physrevlett.86.1849

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