DETERMINATION OF DEFORMATION POTENTIALS IN ZNSE GAAS STRAINED-LAYER HETEROSTRUCTURES/

A method to determine the deformation potentials in strained-layer het erostructures is introduced. This is done by measuring the piezoflecta nce of biaxially strained ZnSe/GaAs layers under additional applicatio n of an external uniaxial stress along the (100) axis. The resulting l owered crystal symmetry yields four dipole-allowed eigenstates for the 1 S exciton. By using a model that includes strain as well as exciton ic spatial dispersion and exchange effects we are able to determine th e internal biaxial strain, the exchange splitting, and the deformation potentials. The numerical results obtained on ZnSe/GaAs heterostructu res as a model system are compared with the deformation potentials giv en by measurements at bulk ZnSe crystals.