VISIBLE AND INFRARED LUMINESCENCE BANDS OF Tm~(3+) IONS IN LiNbO_3 CRYSTAL

摘要

Absorption spectra of Tm~(3+) ions in LiNbO_3 crystal have been investigated at various temperatures between 15 and 296 K, and luminescence spectra observed by excitation into various excited states of Tm~(3+) have been investigated in a spectral region of 400-1750 nm at room temperature. From absorption spectrum at 15 K, it is confirmed that Tm~(3+) ion has C_3 symmetry, indicating that they occupy Li~+ and/or Nb~(5+) sites. The 480, 652, 780, 800, 1220, 1450 and 1650 nm emission bands are observed by excitation into the ~1G_4 state, and the 800, 1450 and 1650 nm emission bands are observed by the excitation into the ~3F_2, ~3F_3 and ~3H_4 states, and the 1650 nm emission band is observed by excitation into the ~3H_5 states. Their optical transition processes are discussed.