Thermally stabilized operating mode of an erbium-ytterbium laser.

We propose a theoretical method of pumping optimization for the Er-Yb laser based on the concept of a self-cooling laser. The pumping optimization realizes the anti-Stokes fluorescence cooling and excitation transfer by the Yb ions simultaneously. In this case, the Yb ions become the sources of cooling while the Er ions remain the heating sources.

Minimization of temperature for laser cooling of Yb-ion-doped crystals.

In this paper, quantum mechanical calculations of cooling characteristics for the Yb:  YLF system with use of the vibronic model of laser cooling are presented. Dynamics of the laser cooling process for the seven-level system of an Yb ion is described by the density-matrix formalism. Dependences of the cooling characteristics on the pump intensity are obtained for various temperatures and absorption coefficients of impurity ions.