Publication # 160

J. A. Cavailles, D. A. B. Miller, J. E. Cunningham, P. Li Kam Wa, A. Miller "Simultaneous measurements of electron and hole sweep-out from quantum wells and modeling of photoinduced field screening dynamics" IEEE J. of Quantum Electronics, 28, 2486-2497 (1992).

Electron and hole escape times from a GaAs-AlGaAs quantum well in an electric field at room temperature are measured by picosecond optical pump-probe techniques on samples containing a single quantum well in a waveguide. The use of a single well avoids multiple well transport and resonant tunneling effects. Carriers excited in the quantum well by the pump beam result in a transient bleaching signal from excitonic saturation, and, as they leave the well, a transient electroabsorption signal because the movement of charge partially screens the electric field. Both processes are modeled, including important electrical equilibration processes of the sample as a whole. This modeling and the use of two samples with asymmetric barrier heights allows the measurement of the electron and hole emission as a function of applied electric field. Preliminary analysis suggests that the emission mechanism is thermionic rather than by tunneling, but the results are not well explained by conventional thermionic emission models

pdf.gif (917 bytes)Full text available for download

[Biographical Information] [Publications] [Home]