Second-harmonic generation in solar-pumped laser

Summary form only given. Solar-pumped lasers are candidates for wireless power transmission in space, free space optical communication, and photochemistry. The broad variety of applications necessitates a spectral coverage between the UV and the IR. Here, we report on second-harmonic generation (SHG) of a solar-pumped laser using a type II KTP crystal in an intracavity Q-switched resonator. Q-switching was obtained either passively by a saturable absorber or actively with an acousto-optic modulator. Concentration of the solar energy that was used to pump the laser was obtained by a 3-stage concentrator; 12 large heliostats, a three-dimensional compound parabolic concentrator (3-D CPC), and a 2-D CPC. A Nd:YAG rod was installed within the reflective 2-D CPC.