[OPTICAL REVIEW Vol. 7, No. 5 (2000) 455-461]
Output Characteristics of High-Power Continuous Wave Raman Fiber Laser at 1484 nm Using Phosphosilicate Fiber
Mahendra PRABHU,1 Nam Seong KIM,1,2 Lu JIANREN1 and Ken-ichi UEDA1
1Institute for Laser Science, University of Electro-Communications, 1-5-1, Chofugaoka, Chofu, Tokyo, 182-8585 Japan, 2Information and Telecommunication Technology Center, the University of Kansas, 2291 Irving Hill Road, Lawrence, Kansas 66045, U.S.A.
(Received March 10, 2000; Accepted June 21, 2000)
A continuous wave (CW) high-power Raman fiber laser (RFL) with maximum output power of 2.24 W and slope effciency of 32.8% at 1484 nm is obtained using a CW 8.4 W/1064 nm Yb-doped double-clad fiber laser as a pump, 700 m phosphosilicate fiber, and cascaded cavities with two pairs of fiber Bragg grating mirrors for the first and the second Stokes orders. Theoretical simulation of the RFL using a very effcient and rapidly converging collocation method is done to understand and optimize the fiber length to obtain maximum second Stokes power. RFL performance for the 300, 700 and 1150 m phosphosilicate fiber lengths was experimentally investigated by observing maximum output power, slope effciency, threshold power, and full-width at half maximum at the second Stokes wavelength.
Key words : Raman fiber laser, phosphosilicate fiber, stimulated Raman scattering, Raman fiber amplifiers, optical fiber communications, optical amplifiers