A semiconductor laser which, with the aid of a nonlinear crystal inside of the laser resonator light of the second harmonic is generated

摘要

A surface-emitting laser with an integral nonlinear crystal. The laser generates light at a fundamental frequency. The nonlinear crystal converts the light into light at twice the fundamental frequency. The laser is configured in a vertical-cavity, surface-emitting structure. An adhesive layer containing indium such as indium gallium phosphide is disposed between a phosphide nonlinear crystal and an arsenide optical amplifier. The optical amplifier and the nonlinear crystal are fused together. The optical amplifier and the nonlinear crystal are located inside a laser cavity that is defined between a pair of reflectors. One of the reflectors is located adjacent the nonlinear crystal and is highly reflective of light at the fundamental frequency but transmissive of light at twice the fundamental frequency. Light is generated at the fundamental frequency, doubled in frequency as it passes back and forth through the nonlinear crystal, and emitted through the reflector adjacent the nonlinear crystal. An intracavity reflector may be included between the optical amplifier and the nonlinear crystal to prevent light at twice the fundamental frequency from propagating from the nonlinear crystal into the optical amplifier.