Photopumped surface-emitting laser provides output continuously tunable over 40 nm
Researchers at Micron Optics Inc. (Atlanta, GA) and Hewlett-Packard Laboratories (Palo Alto, CA) developed a method of continuous-wavelength tuning the output of an optically pumped fiber Fabry-Perot surface-emitting laser over 40 nm. They achieve this by changing the air gap within the laser, which consists of a half-cavity vertical-cavity surface-emitting laser (VCSEL) with a semiconductor distributed Bragg reflector as the bottom mirror and a multiple-quantum-well gain region. The output mirror is either a direct dielectric mirror deposited on the facet of a single-mode fiber or a single-mode fiber waveguide with an embedded mirror.
A combination of a 980-nm-output pump laser and a 980/1300 wavelength-division multiplexer (WDM) was used for continuous optical pumping of the device, which was tunable from 1269.9 to 1309.9 nm at a pump power of about 21 mW. Because this design is built around a fiber, it could prove attractive to designers of telecommunications systems incorporating WDMs.
