BIAS INDEPENDENT HEAVY-HOLE AND LIGHT-HOLE DEGENERACY IN INGAAS INGAASP QUANTUM-WELLS/

We present a type of strained semiconductor quantum-well structure tha t exhibits bias-independent heavy-and light-hole degeneracy. This effe ct is achieved by inserting thin layers of highly strained material in an unstrained quantum well. By adjusting the thickness and the positi on of the highly tensile strained layers, the quantum confined Stark e ffect for the heavy and light holes can be engineered separately to co ntrol the bias dependent polarization properties. Experimental results on such a structure agree well with the theory. These unique bias-dep endent polarization properties have important applications in optoelec tronic devices when specific polarization properties are required. (C) 1998 American Institute of Physics.