Space charge effects on interband optical nonlinearities in asymmetric coupled quantum wells
نویسندگان
چکیده
We have studied space-charge-induced optical nonlinearities for asymmetric coupled quantum wells. By the spatial separation of heavy holes and electrons, an electrostatic potential is induced which increases the fundamental bandgap. Calculations, using the Hartree approximation, for oqtimi5ed AlGaAs structures show that a blue-shift of the band gap of 9 meV at a carrier density of 10 * cm can be obtained. Experimental comparisons with a rectangular well show a large increase in room-temperature nonlinearities.
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