Efficient low-threshold lasers based on an erbium-doped holey fiber

We report experimental results on the continuous-wave lasers based on a small core erbium-doped holey fiber. In a simple Fabry–Pérot-type cavity with high output coupling, we demonstrate low-threshold (0.55 mw) high slope-efficiency (57.3%) operation confirming both the quality and exceptionally high gain efficiency of the fiber. In an all-fiber ring cavity where the cavity loss is reduced, we show that it is possible to achieve a low-threshold laser with extremely wide tunability ( 100 nm around 1550 nm). Our results illustrate some of the unique opportunities provided by active small core holey fibers.K. Furusawa, T. Kogure, J. K. Sahu, J. H. Lee, T. M. Monro, and D. J. Richardso