BROADLY TUNABLE LASER-DIODE-BASED MIDINFRARED SOURCE WITH UP TO 31-MU-W OF POWER AT 4.3-MU-M WAVELENGTH

High-power single-spatial-mode near-IR laser diodes are mixed in perio dically poled LiNbO3 (PPLN) to generate broadly tunable mid IR-radiati on. Conversion efficiencies to the mid IR up to 0.017%/W are demonstra ted, and up to 31 mu W of power is generated at the spectroscopically important 4.3-mu m wavelength. We achieved broadband mid-IR tunability by mixing a wavelength-tunable laser-diode pump source with a fixed-w avelength master oscillator power amplifier laser-diode signal source in a PPLN sample that has a poling period that varies from 21.0 to 22. 6 mu m in the direction transverse to the beam propagation. We generat ed mid-IR radiation from 4.1 to 4.3 mu m with these laser sources, usi ng a fixed 22.0-mu m period region of the sample. (C) 1996 Optical Soc iety of America.