When the interlayer separation is not large, the ground state of a double layer of two-dimensional electron fluids in a large magnetic field is determined by correlations arising from the interlayer Coulomb repulsion. We suggest that, as a consequence, the independent translational invariance of the electrons in each layer is lost, independent of the filling fraction of the Landau levels. The gap measured recently in tunneling across the bilayer is explained and experiments are proposed to test our description.

• Received 16 December 1993

DOI:https://doi.org/10.1103/PhysRevB.49.13999