Abstract

The laser-heated pedestal growth (LHPG) technique is crucible free and can therefore produce high-purity, low-defect density single crystals, which have been shown to be compact and cost- effective as solid-state laser hosts and nonlinear frequency conversion media. However, interface loss is one of the dominant factors that reduce the efficiency of crystal fiber lasers, although cladding by dielectric coating or in-diffusion of the gain core has been used to suppress the interface loss.¹⁻⁵ In this paper, we use a controlled profile of the active ion distribution to confine the laser beam in the center region of the core, and thus reduce the interface loss. As much as 80 mW of laser output power has been achieved with a slope efficiency of 28.9%, which, to our knowledge, is the highest yet achieved for diode-laser pumped crystal fiber Nd:YAG lasers.

© 2002 Optical Society of America