Fedor N. Timofeev and Raman Kashyap of PhotoNova Inc. in Pointe Claire, Quebec, Canada, have reported 300-mW stable single-frequency operation near 976 nm from a laser diode with an external fiber cavity. They described the device, which displayed few mode hops over drive currents from 0 to 500 mA, in the March 24 issue of Optics Express.

The setup employed a 980-nm pigtailed pump laser, with a length of ytterbium-doped fiber and a fiber Bragg grating as the external cavity. Maximum wavelength excursion in the mode-hopping regions was 0.05 nm. Handling the laser and fiber in operation had little effect on performance.