Abstract

Cladding modes in fiber laser technology have considerable interest for dispersion compensation [1] and power scaling [2, 3]. A fiber laser with core-cladding conversion was made in convectional Erbium doped fiber by a combination of Bragg and external cavity mirrors and blocking the fundamental mode with a damaged core fiber [2]. Furthermore, the insertion of two long period gratings (LPG) in a fiber Bragg gratings (FBG) Fabry-Perot cavity has been proposed as a potential high-order-mode fiber laser [3]; however, no experimental demonstration has been reported yet because there are no ring-doped fibers available in the market. In this work, we present the first demonstration of an all-fiber laser with cladding mode feedback based on core-cladding reflections in FBGs, a LPG is used to select a single cladding mode in the cavity. Our approach demonstrates the feasibility of the new concept of lasers proposed in [3].

© 2011 Optical Society of America