Surface acoustic wave controlled charge dynamics in a thin InGaAs quantum well
F. J. R. Schülein, J. Pustiowski, K. Müller×, M. Bichler×, G. Koblmüller×, J. J. Finley×, A. Wixforth, H. J. Krenner
Lehrstuhl für Experimentalphysik 1 and Augsburg Centre for Innovative Technologies (ACIT), Universität Augsburg, 86159 Augsburg, Germany
Center for NanoScience CeNS, 80539 München, Germany
×Walter Schottky Institut and Physik Department, Technische Universität München, 85748 Garching, Germany
Abstract
We experimentally study the optical emission of a thin quantum well and its
dynamic modulation by a surface acoustic wave (SAW). We observe a characteristic
transition of the modulation from one maximum to two maxima per SAW cycle as the
acoustic power is increased which we find in good agreement with numerical calculations
of the SAW controlled carrier dynamics. At low acoustic powers the carrier mobilites limit
electron-hole pair dissociation, whereas at high power levels the induced electric fields
give rise to efficient acousto-electric carrier transport. The direct comparison between the
experimental data and the numerical simulations provide an absolute calibration of the
local SAW phase.