Magnetoreflection Studies in Arsenic

An infrared magnetoreflection study has been made of the trigonal face of single-crystal arsenic. Oscillations of very large amplitude have been observed with a line shape quite unlike any previously reported. It has been found that the complicated line shape can be understood by assuming that the oscillations are associated with interband transitions between a pair of coupled bands at a point of low symmetry (point $Q$) in the Brillouin zone. On the basis of this assumption, the data can be interpreted to obtain various band parameters such as the energy gap and the cyclotron effective mass. Some observed nonparabolic effects can also be explained. The magnetoreflection data for the trigonal face are found to be consistent with Lin and Falicov's arsenic energy-band model.