Electron-phonon interaction in Tm(3+), Ho(3+), and Dy(3+) doped BaY(2)F(8) single crystals

High resolution Fourier transform spectroscopy is applied in a wide wave number range (500-24,000 cm(-1)) to investigate the electron-phonon interaction in Dy(3+), Tm(3+), and Ho(3+) doped BaY(2)F(8) single crystals. The shape, position, and width of the zero phonon (ZP) absorption lines induced by RE(3+) ions are carefully analyzed in the 9-300 K range. The line shift and broadening are discussed in the framework of a two phonon Raman scattering model and the electron-phonon coupling constants are obtained as fitting parameters. The interaction between the RE(3+) ion and the surrounding matrix is unveiled also by weak vibronic lines accompanying the ZP ones. (C) 2008 Elsevier B.V. All rights reserved.