We demonstrate a 1.5-µm - wavelength fiber laser formed by placement of glass microsphere resonators along a fiber taper. The fiber taper serves the dual purpose of transporting optical pump power into the spheres and extracting the resulting laser emission. A highly doped erbium:ytterbium phosphate glass was used to form microsphere resonant cavities with large gain at 1.5µm . Laser threshold pump powers of 60μW and fiber-coupled output powers as high as 3 μW with single-mode operation were obtained. A bisphere laser system consisting of two microspheres attached to a single fiber taper is also demonstrated.
© 2000 Optical Society of America
(060.2380) Fiber optics and optical communications : Fiber optics sources and detectors
(140.0140) Lasers and laser optics : Lasers and laser optics
(140.3500) Lasers and laser optics : Lasers, erbium
(140.3510) Lasers and laser optics : Lasers, fiber
M. Cai, O. Painter, K. J. Vahala, and P. C. Sercel, "Fiber-coupled microsphere laser," Opt. Lett. 25, 1430-1432 (2000)