We report on the laser properties of multicore photonic crystal fiber lasers. A stable phase locking of six- and seven-core structures through evanescent coupling is observed. Effective supermode selection is obtained by using both diffraction losses and the Talbot effect. A pure in-phase supermode is obtained (1.1 times diffraction limited). The laser operating in this mode has a slope efficiency of 70% with up to 44 W of output power. The modal area of the in-phase supermode multicore fiber is 1150 µm², which makes it, to our knowledge, the single-mode fiber laser with the largest mode field area. In-phase laser action is stable when the fiber is bent.
© 2005 Optical Society of America
(050.1940) Diffraction and gratings : Diffraction
(070.6760) Fourier optics and signal processing : Talbot and self-imaging effects
(140.3290) Lasers and laser optics : Laser arrays
(140.3510) Lasers and laser optics : Lasers, fiber
L. Michaille, C. R. Bennett, D. M. Taylor, T. J. Shepherd, J. Broeng, H. R. Simonsen, and A. Petersson, "Phase locking and supermode selection in multicore photonic crystal fiber lasers with a large doped area," Opt. Lett. 30, 1668-1670 (2005)