TUNNELING AND ENERGY-TRANSFER IN ZNSE-BASED SEMIMAGNETIC DOUBLE-QUANTUM WELLS

An asymmetric double-quantum-well structure has been fabricated by mol ecular-beam epitaxy, consisting of a semimagnetic (Zn,Cd,Mn)Se and a n onmagnetic (Zn,Cd)Se well, weakly coupled via a ZnSe barrier. Level cr ossing of the quantum well excitons is accomplished through an externa l magnetic field. The crossing is accompanied by reverse of the tunnel ing direction. The tunneling process is of excitonic nature. Besides t he very efficient 2-LO-phonon scattering mechanism, indications for a radiationless resonance energy-transfer have been found. [S0163-1829(9 8)03823-5].