Optical properties of InSb between 300 and 700 K. II. Magneto-optical experiments.

To study the InSb band structure at high temperatures we have measured the far-infrared transmission as a function of magnetic field up to 20 T at temperatures between 300 and 700 K. The increasing carrier density with temperature leads to an increase of the plasma frequency which means that the magneto-optical response evolves from single-particle cyclotron resonance at room temperature to magnetoplasma effects, like helicon waves at the highest temperature. The experimental data can be ex plained using known theories about magneto-optical response, carrier statistics, and band structure, provided the band-edge effective mass is temperature dependent