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