Time Resolved Spectroscopy of GaAs/AlGaAs Quantum Well Structures
Optical spectroscopic techniques like absorption, photoluminescence, and photoluminescence excitation spectroscopy are widely used to characterize and investigate the properties of quantum wells (QW) and provide significant information on the electronic structure of the respective samples. Conclusions on the dynamics of nonequilibrium carriers, however, generally cannot be drawn from stationary experiments but require time resolved spectroscopy techniques. The dependence of the fundamental relaxation and recombination processes on the dimensionality, i.e. the thickness LZ and Lb of the quantum well and barrier layers, respectively, is one of the key questions as far as QW are considered. In addition, new relaxation processes come into play in QW, which are not present in bulk material, like carrier trapping from the barriers into the QW, intersubband scattering between states with different quantum number, and intervalley scattering including spatially seperated bands (real space transfer).
Unable to display preview. Download preview PDF.
- 4.Recent results on hot carrier cooling in GaAs QW can be found e.g. in: K. Leo, W.W. Rühle, H.-J. Queisser, K. Ploog, Appl. Phys. A 45, 35 (1988)Google Scholar
- 6.P. Dawson, B.A. Wilson, C.W. Tu, R.C. Miller, Appl. Phys. Lett.48,541 (198)Google Scholar
- 7.P. Dawson, K.J. Moore, C.T. Foxon, SPIE, 782 Quantum Well and Superlattice Physics, 208 (1987)Google Scholar
- 9.K.K. Bajaj, same issueGoogle Scholar
- 10.V.C. Chang, same issueGoogle Scholar
- 11.Y. Masumoto, M. Matsuura, S. Tarucha, H. Okamoto, Phys. Rev. B52, 4275 (1985)Google Scholar