Anisotropic Drude Reflectivity of Ag₂F Crystal

抄録

Large single crystals of Ag₂F have been grown and anisotropic electrical conductivity and optical reflectivity have been measured. The dc conductivity along the c-axis is about one tenth of that in the c-plane and its temperature dependence is metallic. Reflectivity spectra have been observed from 0.05 to 30 eV with linearly polarized light whose electric vectors are perpendicular and parallel to the c-axis. Clear anisotropic reflectivity due to the conduction electrons has been found with the sharp Drude edges at 2.9 and 0.9 eV in the perpendicular and parallel directions, respectively. The analysis of the results does not give a quantitative support to the two Fermi surface model proposed by Hamada et al. Absorption spectra in the interband transition region above the Drude edges also show anisotropy.