The electron effective mass in indium antimonide was measured at temperatures between 4.2 and 138 K using far-infrared cyclotron resonance at magnetic fields of 14.08, 16.09, and 18.05 kOe. The effective mass exhibits a maximum at 55 K which is 0.4% above the mass at 4.2 K and decreases with increasing temperature above 55 K. This behavior is explained reasonably well by the temperature dependence of the dilational component of the change in energy gap between the conduction and valence bands using Kane's equation for the band-edge effective mass. There is a small discrepancy between the dilational and measured mass change. Possible causes of this discrepancy are discussed.

• Received 17 September 1973

DOI:https://doi.org/10.1103/PhysRevB.9.568