Longitudinal Photon Drag in p‐Type Tellurium

The longitudinal photon drag has been studied for free holes in tellurium using a Q‐switched CO 2 laser. A great effect is expected due to the great interband matrix element for allowed direct hole transitions between the sub‐valence bands H 4 and H 5 . Due to the low crystal symmetry interesting anisotropy phenomena take place. The measurements have been performed for a set of samples, oriented either parallel or perpendicular to the c ‐axis. The drag effect connected with sub‐band transitions is dominating as predicted by the theory (tensor coefficient σ 1133 = 5 × 10 −12 cm/V at T = 77 K). The coefficient σ 3311 connected with the absorption of radiation polarized F ω ⊥ c was found to be −1 × 10 −12 cm/V at 77 K.