Photoluminescence up-conversion in InAsÕGaAs self-assembled quantum dots
نویسندگان
چکیده
We report up-converted photoluminescence in a structure with InAs quantum dots embedded in GaAs. An efficient emission from the GaAs barrier is observed with resonant excitation of both the dots and the wetting layer. The intensity of the up-converted luminescence is found to increase superlinearly with the excitation density. The results suggest that the observed effect is due to a two-step two-photon absorption process involving quantum dot states. © 2000 American Institute of Physics. @S0003-6951~00!02232-4#
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