2-PHOTON SPECTROSCOPY IN ZNSE ZNS QUANTUM-WELLS/

We have studied the electronic structure of strained-layer ZnSe/ZnS su perlattices by using two kinds of two-photon spectroscopy: two-photon absorption spectroscopy and resonant second-harmonic generation. The e xciton binding energy is found to exhibit a blue shift as compared to the bulk value due to the exciton confinement effect. Based on the obs erved subband energies, we derive a conduction-band offset of approxim ately 70 meV and a valence-band offset of approximately 800 meV.