Pressure-dependent magnetoreflection studies of Bi and Bi1-xSbx alloys

Pressure-dependent magnetoreflection results for Bi and Bi1-xSbx (x=0.05,0.15) alloys are reported for pressures up to 3 kbar at 77 K, for H parallel to the binary axis and using a CO2 laser source operating at 10.6 m. The results are interpreted to yield values for the pressure dependence of the L-point energy gap and the band-edge cyclotron effective mass. The analysis shows that the pressure dependence of Egmc* dominates the pressure-dependent magnetoreflection spectra, a result of significance because previous pressure-dependent Fermi-surface studies have assumed Egmc* to be pressure independent. Furthermore, the analysis shows that the magnitudes of the individual pressure derivatives dEgdp and dmc*dp are very sensitive to d(Egmc*)dp for these materials.