A symmetrically doped double layer electron system with total filling fraction Î½ = 1/m decouples into two even denominator (Î½ = 1/2m) composite fermion â€˜metalsâ€™ when the layer spacing is large. Out-of-phase fluctuations of the statistical gauge fields in this system mediate a singular attractive pairing interaction between composite fermions in differentâ€¦ (More)

The reduction of the energy gap due to Landau level mixing, characterized by the dimensionless parameter Î» = (e/Ç«l0)/hÌ„Ï‰c, has been calculated by variational Monte Carlo for the fractional quantum Hall effect at filling fractions Î½ = 1/3 and 1/5 using a modified version of Jainâ€™s composite fermion wave functions. These wave functions exploit the Landauâ€¦ (More)

Spin-orbit corrections to superexchange are calculated using the method of Moriya [T. Moriya, Phys. Rev. 120 91, (1960)] for two of the insulating parent compounds of the cuprate superconductors: (1) La2âˆ’xNdxCuO4 where the CuO6 octahedra forming each Cu-O layer are tilted in staggered fashion about an axis which depends on x and temperature; and (2)â€¦ (More)

To leading order in displacement size, the scattering of electrons in a Cu-O plane from O displacements perpendicular to that plane is due to spin-orbit coupling. This scattering is investigated with the following results: (1) As a consequence of timereversal symmetry, spin fluctuations, which can strongly enhance scattering from a spin impurity, do notâ€¦ (More)