Near-band-gap reflectance anisotropy in orderedP
- 15 June 1997
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 55 (24), 16385-16389
- https://doi.org/10.1103/physrevb.55.16385
Abstract
We present a theory that models the reflectance difference spectrum of bulk, spontaneously ordered P. Near the band gap this spectrum exhibits a sharp, negative feature at and a broad positive feature that peaks near +. The zero crossing between these two peaks occurs near +. For the sample studied in this paper, the spin-orbit splitting and the crystal-field splitting are 120 and 25 meV, respectively. Two previous calculations, which assume constant transition-matrix elements, were able to produce a negative peak at , but not the positive feature. In this paper, the reflectance difference spectrum near the band gap is calculated using an 8-band k⋅p model and an explicit treatment of the momentum or k dependence of the transition-matrix elements. The new calculation produces both the negative peak at and the positive feature that peaks near +. The positive feature is attributed to the strong k dependence of the matrix element anisotropy. A strong coupling, enhanced by ordering, between three valence bands is essential. A problem associated with the analytical expression for the dielectric function ɛ used in previous calculations is discussed.
Keywords
This publication has 28 references indexed in Scilit:
- Band-gap reduction and valence-band splitting of ordered GaInP2Applied Physics Letters, 1995
- Photoluminescence, photoluminescence excitation, and resonant Raman spectroscopy of disordered and ordered Ga0.52In0.48PJournal of Applied Physics, 1993
- Partial-ordering effects inPPhysical Review B, 1993
- Photoluminescence-excitation-spectroscopy studies in spontaneously orderedPhysical Review B, 1993
- Evolution of alloy properties with long-range orderPhysical Review Letters, 1992
- Metalorganic chemical vapor deposition growth of Ga0.5In0.5P ordered alloys by phosphine modulationJournal of Crystal Growth, 1992
- Valence-band splitting in orderedP measured by polarized photoluminescence excitation spectroscopyPhysical Review B, 1992
- Excitation intensity dependence of photoluminescence in Ga0.52In0.48PApplied Physics Letters, 1990
- Polarized band-edge photoluminescence and ordering inPPhysical Review Letters, 1989
- Evidence for the existence of an ordered state in Ga0.5In0.5P grown by metalorganic vapor phase epitaxy and its relation to band-gap energyApplied Physics Letters, 1987