High-power multiple-frequency narrow-linewidth laser source based on a semiconductor tapered amplifier

The output of two grating-stabilized external-cavity diode lasers was injected into a semiconductor tapered amplifier in a master oscillator-power amplifier (MOPA) configuration. At a wavelength of 671 nm this configuration produced 210 mW of power in a diffraction-limited mode with two frequency components of narrow linewidth. The frequency difference delta was varied from 20 MHz to 12 GHz, while the power ratio of the two components was freely adjustable. For delta < 2 GHz additional frequency sidebands appear in the output of the MOPA. This configuration is a flexible and simple high-power cw laser source for light with multiple narrow-linewidth frequency components. (C) 1999 Optical Society of America.