Growth and magnetooptical properties of anisotropic TbF3 single crystals

This paper investigates the Faraday effect and absorption and luminescence spectra of single-crystal TbF3 measured at 90 K and 300 K. The optical-quality single-phase TbF3 crystals (structural type β-YF3) were grown by the Bridgman technique. Faraday rotation angles were measured at remagnetization along the [100] crystallographic axis. Low temperature optical measurements were carried out along the [100] axis. “Quasi-doublet” sublevels with energy at 0 cm−1, 65 cm−1, and 190 cm−1, and also a singlet sublevel with energy at 114 cm−1 located in the ground 7F6 multiplet were determined from the low temperature luminescence spectra. The Van-Vleck behavior of the magnetic susceptibility χb can be satisfactorily explained by the magnetic mixing of wave functions belonging to the ground and first excited “quasi-doublet” sublevels at 0 and 65 cm−1, respectively. Analysis of the oscillation dependences of the rotation angle showed that the value of the natural birefringence (Δn ≈ 0.0186) remains nearly constant w...