Magnetism and Josephson effect in a coupled quantum well electron-hole system

We investigate the magnetic properties and Josephson-type effects in a two-layer system of spatially separated electrons (e) and holes (h) with pairing in coupled quantum wells, taking into account interlayer tunnelling. If the external magnetic field is lower than the critical one (H-cl), the system is a weak diamagnet (the magnetic field between the layers of the system is weakened by the currents flowing along the layers). If the external magnetic field exceeds H-cl, the ground state of the system is the mixed state: vortices of the magnetic field (analogous to those in the superconducting Josephson contact) penetrate into the space between the layers. The analog of the Josephson effect in the system of spatially separated electrons and holes with pairing is also considered. (C) 1997 Published by Elsevier Science B.V.