Galvanomagnetic Effects inp-Type Indium Antimonide

The conductivity and Hall effect of $p$-type InSb have been measured as a function of magnetic field strength and of temperature. The behavior of the Hall coefficient and the magnetoresistance at 78°K is consistent with a valence band which consists of two bands with different effective masses and has degenerate maxima at the center of the Brillouin zone. Negative magnetoresistances have been observed at liquid helium temperatures; the effect is positive, however, for very pure samples when the magnetic field strength exceeds ∼${10}^3$ gauss. The conduction mechanism in this temperature range is still poorly understood.