Radial-pumped microchip high-power composite Yb : YAG laser: Design and power characteristics

We present a novel architecture for a quasi-four-level diode-pumped high-po wer microchip laser. The design uses a Yb:YAG core surrounded by an undoped YAG region of slab or disk shape, and that can be pumped from one side (un symmetrical pumping) or from both slab sides (symmetrical pumping). Theoret ical descriptions of the pumping optimization. pump-beam distribution, and output-to-input power characteristics are presented. The simulations show t hat from a composite Yb:YAG chip, which consists of a Yb:YAG core of 2.0-mm diameter and 13.0-at.% Yb concentration surrounded by an undoped YAG slab of 5.0-mm width and 0.8-mm thickness, a TEM00 output beam of 100W continuou s-wave power could be obtained. The expected optical-to-optical efficiency is 39%.