Abstract

The need for sources compatible with today’s fiber-optic communication systems has led to the investigation of rare earth-doped monomode fibers as an active medium. Neodymium-doped silica fibers are readily pumped by common laser diodes, but with the limited power available in single-stripe devices, the power from the fiber laser has been limited to a few milliwatts. By using an injection-locked diode array it is possible to get a diffraction-limited high-power beam to use as a pump source for the fiber laser. Fiber laser output powers of up to 15-mW cw have been obtained using this method. If an acoustooptic modulator is inserted in the cavity, pulses as short as 120 ps are produced. It is expected that if an all-fiber modulator is used, the cavity losses will be reduced along with the pulse width. The laser can also be operated in a Q-switched mode by inserting an acoustooptic deflector into the cavity as well. The laser was allowed to prelase prior to Q-switching which maintained the pulse width, and the peak power in the output train was increased to 1 kW. This power should be sufficient to produce nonlinear effects in the fiber.

© 1988 Optical Society of America