Abstract

Semiconductor flared amplifiers now routinely emit ~1 watt of light in a diffraction-limited, single-frequency beam when driven at currents of a few amps.¹ However, if driven at higher currents, the output beam breaks into filaments that spread light into higher-order modes.² Here we present a simple method for extracting a diffraction-limited beam from the highly-filamented output of a semiconductor amplifier. With this method we can now operate the amplifiers at currents 3-4 times their diffraction-limited range and still obtain a diffraction-limited beam. By combining the outputs of multiple amplifiers, this method should produce very high power diffraction-limited beams from semiconductor lasers.

© 1996 Optical Society of America