Growth of Yb3+-doped YLiF4 laser crystal by the Czochralski method.: Attempt of Yb3+ energy level assignment and estimation of the laser potentiality

YLiF4 (YLF) single crystals undoped and Yb3+-doped with different concentrations were grown by the Czochralski technique under CF4 atmosphere. Detailed analysis of Yb3+-doped YLF spectroscopy were made to contribute to the determination of energy levels in this host. We are dealing with temperature and concentration dependences of both pi and sigma polarizations of the infrared (IR) absorption and emission spectra. Raman spectra were also used to give an attempt of interpretation of electronic and vibronic levels. The radiative energy transfer (self-trapping) and strong phonon-electron coupling make the assignment of Yb3+ energy levels difficult. Evaluation of the laser potentiality of this fluoride host is also presented. (C) 2004 Elsevier B.V. All rights reserved.