Time-resolved photoluminescence from hot two-dimensional carriers in GaAsGaAlAs MQWS
Surface Science 170:1-2 (1986) 511-519
Abstract:
Picosecond time-resolved measurements of luminescence from hot carriers confined in GaAsGaAlAs multiple quantum wells show that energy loss rates are substantially slower than those predicted for 2D carriers. We review our recent experiments and present results for photoexcitation of (1) GaAs layers only, (2) both GaAs and GaAlAs layers. We compare the energy loss rates in samples with different well widths. Finally, we present measurements of hot 2D carrier relaxation in the presence of high magnetic fields; at low fields the energy loss rate is reduced, but for B > 9 T we observe a rapid increase. © 1986.TIME-RESOLVED PHOTOLUMINESCENCE FROM HOT TWO-DIMENSIONAL CARRIERS IN GAAS-GAALAS MQWS
SURFACE SCIENCE 170:1-2 (1986) 511-519
Determination of domain wall structures in thin foils of soft magnetic alloy
Journal of Magnetism and Magnetic Materials 49:3 (1985) 277-285
Abstract:
Domain wall structures in thin foils of a Ni-Fe-Co-Ti alloy have been determined using the differential phase contrast mode of Lorentz electron microscopy. Among the advantages of this mode are that easily interpretable signals can be obtained whilst the experiment is in progress. In accord with theoretical expectation the walls were found to have a vortex structure whose width increased linearly with foil thickness. © 1985.Picosecond photoluminescence measurements of Landau level lifetimes and time dependent Landau level linebroadening in modulation-doped GaAs-GaAlAs multiple quantum wells
Physica B+C 134:1-3 (1985) 318-322
Abstract:
We report the first picosecond time-resolved photoluminescence measurementsof hot-carrier relaxation in a modulation-doped GaAs-GaAlAs MQW in the presence of strong magnetic fields. We have measured the lifetimes of carriers in excited Landau levels and have determined the time-dependent carrier temperature. We find that the cooling rate is slower in applied field tthan at B=0; also there is a significant increase in the cooling rate for B {greater-than or approximate} 10T. We report also the observation of highly time-dependent linewidths of the Landau levels. © 1985.Hot Electron Relaxation and Trapping in Modulation — Doped GaAs/GaAlAs Multiple Quantum Well Heterostructures
Springer Nature (1985) 567-570