Intensity dependent time-resolved photoluminescence studies of GaN/AlGaN multiple quantum wells of varying well width on laterally overgrown a-plane and planar c-plane GaN

Garrett, GA
Shen, H
Wraback, M
İmer, Muhsine Bilge
Haskell, B
Speck, JS
Keller, S
Nakamura, S
DenBaars, SP
GaN/AlGaN multiple quantum wells (MQWs) of varying well width grown on planar c-plane GaN and a-plane GaN templates fabricated by lateral epitaxial overgrowth (LEO) have been studied by subpicosecond photoluminescence (PL) downconversion and time-correlated single photon counting as a function of pump intensity. Although slower room temperature decays at higher carrier density are observed in both a-plane LEO and c-plane MQWs with 3 nm well width, this behavior is attributed to suppression of electric field-enhanced recombination through the barriers and interfaces at higher carrier density in the c-plane MQW, while in the a-plane LEO MQW the sublinear dependence of the PL signal at t = 0 on pump intensity implies that the radiative lifetime in this high quality sample increases due to a reduction in excitonic oscillator strength associated with phase space filling. The combination of more intense time-integrated PL spectra and shorter PL lifetimes with decreasing well width in the a-plane LEO MQWs for low pump intensity suggests that the radiative lifetime becomes shorter due to the accompanying increase in exciton binding energy and oscillator strength at smaller well width. (c) 2005 WILEY-VCH Verlag GmbH & Co.


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Structural and optical properties of 75 mol % Ga2Se3 - 25 mol % Ga2S3 system of single crystals were investigated by experimental techniques of x-ray diffraction (XRD), energy dispersive spectroscopy, Raman spectroscopy and ellipsometry. XRD pattern indicated that the studied compound has crystalline nature with cubic structure. Vibrational modes in the crystal were revealed using Raman spectroscopy experiments in the 90-450 cm(-1) frequency range and nine modes were observed in the spectrum. Ellipsometry m...
Citation Formats
G. Garrett et al., “Intensity dependent time-resolved photoluminescence studies of GaN/AlGaN multiple quantum wells of varying well width on laterally overgrown a-plane and planar c-plane GaN,” PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, pp. 846–849, 2005, Accessed: 00, 2020. [Online]. Available: