Optical Anisotropy of RMnO3 Manganites in the Range of 4f-4f Transitions

Optical absorption of orthorhombic and hexagonal manganites RMnO3 (R= Pr3+, Gd3+, Sm3+, Eu3+, Ho3+, Tm3+, Er3+, and Yb3+) were studied in polarized light in the near- and mid-infrared range for the temperature range 80 - 300 K. Several spectral features associated with 4f-4f transitions of R3+ ions were found in the transparency window of RMnO3. Anisotropy of the absorption spectra in the range of multiplet 4f-4f transitions and changes in populations of the multiplet levels with temperature were observed.