Abstract
We have obtained the three independent complex components (ω), (ω), and (ω) of the linear piezo-optical tensor (ω) [Δ(ω)=(ω)] of GaAs in the ∼1.5–5.4-eV photon-energy range (visible UV) by applying static uniaxial stress (X) along the high-symmetry directions [100] and [111] and measuring the stress-induced changes in the dielectric function ε(ω). These measurements were performed using a conventional rotating analyzer ellipsometer at room temperature. The measured components of the piezo-optical tensor are in agreement with prior Kramers-Kronig analysis of piezoreflectance data. Each component of (ω) is also compared with band-structure-based calculations performed with the empirical pseudopotential method. The calculations are in reasonable agreement with the experiment. Improved deformation-potential constants , , , and for the -+ transitions were also obtained from an analysis of the ellipsometric data. They compare favorably with theoretical estimates. In particular, the experimental value of agrees rather well with band-structure-based calculations, in contrast with previous measurements of this parameter.
- Received 23 July 1992
DOI:https://doi.org/10.1103/PhysRevB.46.15139
©1992 American Physical Society