Burstein-Moss shift of n-doped (formula presented)

Abstract

We have evaluated the Burstein-Moss (BM) shift at 300 K in seven samples of (formula presented) (formula presented) lattice matched to InP using spectral ellipsometry in the range of 0.4–5.1 eV. The data have been fitted over the entire spectral range to a model reported by Holden et al. [in Thermphotovoltaic Generation of Electricity, edited by T. J. Coutts, J. P. Brenner, and C. S. Allman, AIP Conf. Proc. No. 460 (AIP, Woodbury, NY, 1999), p. 39], based on the electronic energy-band structure near critical points plus relevant discrete and continuum excitonic effects. A Fermi-level filling factor in the region of the fundamental gap has been used to account for the BM effect. While our data exhibit nonparabolic effects, with a blueshift of 415 meV for the most highly doped sample, we did not observe the Fermi-level saturation at 130 meV for (formula presented) reported by Tsukernik et al. [Proceedings of the 24th International Conference on the Physics of Semiconductors, Jerusalem, 1998, edited by D. Gershoni (World Scientific, Singapore, 1999)]. Our BM displacements are in agreement with a modified full-potential linearized augmented-plane-wave calculation [G. W. Charache et al., J. Appl. Phys. 86, 452 (1999)] plus possible band-gap-reduction effects. © 2001 The American Physical Society.