Abstract

In this paper we report on the absorption saturation study of the Mg₂SiO₄:Cr⁴⁺ and Y₂SiO₅:Cr⁴⁺ in visible band of wavelength. We study the forsterite samples having orientations E // c and E // b. In this case, the absorption band in forsterite are located at 570 - 720 nm (for E // c forsterite) and at 690 - 780 nm (for E // b forsterite). The orientations of the Y₂SiO₅: Cr⁴⁺ sample and the light polarization were chosen to provide strong absorption at 694 nm. These absorption bands in both crystals are assigned to transition from the ³A₂ ground state of the Cr⁴⁺ to the crystal field components of the ³T₁ (³F) excited state splitted due to symmetry distortion of the ${\text{CrO}}_4^{4-}$ tetrahedron.

© 1995 IEEE