Investigations of quantum wires, carrier diffusion lengths, and carrier lifetimes in GaAs/AlGaAs heterostructures

• Main Author: Zarem, Hal
• Format: Others
• Language: en
• Published: 1990
• Online Access: https://thesis.library.caltech.edu/4479/1/Zarem_h_1990.pdf; Zarem, Hal (1990) Investigations of quantum wires, carrier diffusion lengths, and carrier lifetimes in GaAs/AlGaAs heterostructures. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/ajzc-wx87. https://resolver.caltech.edu/CaltechETD:etd-11092007-090251 <https://resolver.caltech.edu/CaltechETD:etd-11092007-090251>

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. Nanometer scale wire structures are fabricated by selective disorder of a GaAs/AlGaAs quantum well. These structures are investigated by cathodoluminescence (CL). Spectrally resolved CL images of the structures as well as local CL spectra of the structures are resented. The effects of fabricational variations on quantum wire laser gain spectra and performance are discussed. A new technique for determining carrier diffusion lengths by cathodoluminescence measurements is presented. The technique is extremely accurate and can be applied to a variety of structures. The ambipolar diffusion length and carrier lifetime are measured in [...] for several mole fractions in the interval 0 < [...] < 0.38. These parameters are found to have significantly higher values in the higher mole fraction samples. These increases are attributed to occupation of states in the indirect valleys, and supporting calculations are presented.