STARK-EFFECT NEAR THE TYPE-I-TYPE-II TRANSITION POINT IN SEMICONDUCTOR QUANTUM-WELLS

We show the effect of an electric field normal to the quantum-well (QW ) plane on the shape of a hole wave function in the vicinity of the ty pe-I-type-II transition point, which leads to (i) the strong decrease of the oscillator strength of e1h1, e1h3 exciton states, and (ii) an i ncrease in the strength of the e1h2 transition, which is forbidden in the absence of the field. The variational calculation of the hole wave function in a type-II QW reveals the existence of some critical elect ric field which initiates a shift of the hole center of mass to one of the interfaces.