Role of monovalent alkali ions in the Yb3+ centers of CaF2 laser crystals

Yb3+ and M+ monovalent alkali ions (M+ = Li+, Na+, K+)-co-doped CaF2 cubic laser crystals were grown by the micro-pulling-down method (μ-PD) under CF4 atmosphere. Structural and spectroscopic characterizations of Yb3+ in substitution of Ca2+ (absorption, emission and decay curves) were carried out to study the effect of M+ ions as charge compensators.