Optical investigation of ~6A_(1g)(~6S) - > ~4T_(2g) (~4D) absorption band in magnetic MnF_2 and RbMnF_3 compounds

摘要

Spectroscopic measurements of the spectral lines in MnF_2 and RbMnF_3 have been carried out in the temperature range 10-300 K. Observations of exciton-magnon sidebands in the fine structures of the ~6A_(1g) - > ~4T_(2g) (~4D) state of Mn~(2+) ions are reported at low temperatures. The temperature dependence of peak positions, oscillator strength and half line widths have been investigated for selected bands. The analysis of the temperature dependence of these parameters confirms that the fine structure of the D band is mainly attributed to spin-orbit interaction combined with spin multiplicity in the ordered state. The ratios for the separation energies between these lines are fitted with the ratios expected from Lande interval rule.