EFFECTS OF INTERFACE ASYMMETRY ON HOLE SUBBAND DEGENERACIES AND SPIN-RELAXATION RATES IN QUANTUM-WELLS

We consider the subband dispersions and the spin relaxation times for holes in semiconductor heterostructures without a common atom. We show that the interface asymmetry in such structures leads to a breaking o f the parity degeneracy of the Luttinger dispersions. We calculate tha t the resulting spin splitting induces a D'yakonov-Perel' spin relaxat ion mechanism that can be up to five orders of magnitude faster than t he one considered hitherto.