The Optical Activity of Tellurium

The optical activity (o. a.) of tellurium samples with carrier concentrations from 10′4 to 3 x × 1018 cm‐3 is measured between 4 and 300 K. A comparison with the circular dichroism of the band edge shows that the 0.a. is mainly related to interband transitions near the energy gap. The experimental results are interpreted using a quantum‐mechanical model, which allows a calculation of the o.a. from the energy bands and matrix elements. The undoped samples show a characteristic temperature dependence of the o. a., which is caused by the temperature dependence of the energy gap. At low temperatures in degenerate samples depopulation effects in the o.a. are observed.