1. J. K. Furdyna and J. Kossut, in Semiconductors and Semimetals, edited by R. K. Willardson and A. C. Beer (Academic, Boston, 1988), Vol. 25.
2. J. W. Richardson and G. J. M. Janssen, Phys. Rev. B 39, 4958 (1989).
3. D. S. McClure, J. Chem. Phys. 39, 2850 (1963).
4. D. Langer and S. Ibuki, Phys. Rev. 138, A809 (1965).
5. H. E. Gumlick, R. L. Pfrogner, J. C. Shaffer, and F. E. Williams, J. Chem. Phys. 44, 3929 (1966).