We report on recent experiments investigating the modification of theinter-band optical response of a piezoelectric semiconductor quantum wellstructure under the influence of intense short period surface acoustic waves.Experimentally, we study the photoluminescence (PL) of an undoped strainedInGaAs/GaAs quantum well on which surface acoustic waves are propagated in theGHz regime. We observe a pronounced influence on the PL, both in intensity aswell as in energetic position: Above a critical acoustic power density andcorresponding lateral piezoelectric field strength, we observe a quenching ofthe excitons resulting in a strong decrease of the PL intensity. Using twotransducers in a cavity resonator geometry, we can create a standing surfaceacoustic wave and hence control the nature and efficiency of the acoustictransport of the photoexcited electrons and holes.
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