Nonparabolicity and Effective Masses of Conduction Electron in InχGa1-χAs Alloys

Y. T. Dai ； J. L. Shen ； Y. F. Chen ； S. Z. Chang ； S. C. Lee

《Chinese Journal of Physics》 36卷1期 (1998/02) Pp. 20-26

並列摘要

We report an investigation of the compositional dependence of the conduction band effective masses in InxGa1-xAs alloys at different laser energies determined by FIR magneto-photoconductivity measurements. It is found that the effective mass increases with increasing laser energy due to the effect of band nonparabolicity. The obtained nonparabolicity and the band-edge effective mass are found to be larger than those predicted from k p perturbation theory. This result can be successfully explained if the effect of the wave-function mixing between conduction and valence bands due to alloy disorder is taken into account. We point out that the strength of the potential fluctuations induced by alloy disorder is dominated by the electronegativity difference between the mixed elements.