Highelandau levels and electron correlation

Abstract

Exact diagonalization of the Hamiltonian is employed to study the ground state of double-layer system in which a higher Landau level in one layer is degenerate with the ground Landau level in the other. It is shown that electrons form bound pairs over a wide range of layer separations and filling factors. The binding is due to the attraction between an electron in the low-density layer and the interior of the larger cyclotron orbit in the high-density layer. Results from exact diagonalization are reinforced by an approach using the analytical model wave functions.