SUPERFLUIDITY OF INDIRECT MAGNETOEXCITONS IN COUPLED QUANTUM-WELLS

The temperature T-c of the Kosterlitz-Thouless transition to a superfl uid state for a system of magnetoexcitons with spatially separated ele ctrons e and holes h in coupled quantum wells is obtained as a functio n of magnetic field H and interlayer separation D. It is found that T- c decreases as a function of H and D at fixed exciton density n(ex) as a result of an increase in the exciton magnetic mass. The highest Kos terlitz-Thouless transition temperature as a function of H increases ( at small D) on account of an increase in the maximum magnetoexciton de nsity n(ex) versus magnetic field, where n(ex) is determined by a comp etition between the magnetoexciton energy and the sum of the activatio n energies of incompressible Laughlin fluids of electrons and holes. ( C) 1997 American Institute of Physics.