An all-fiber approach for in-phase supermode phase-locked operation of multicore fiber lasers

Abstract

ABSTRACT An all-fiber approach is utilized to phase lock and select the in-phase supermode of compact multicore fiber lasers. Based on the principles of Talbot imaging and waveguide multimode interference, the fundamental supermode is selectively excited within a completely monolithic fiber device. The all-fiber device is constructed by simply fusion splicing passive non-core optical fibers of controlled lengths at both ends of a piece of multicore fiber. Experimental results upon in-house-made 19- and 37-core fibers are demonstrated, which generate output beams with high-brightness far-field intensity distributions. The whole fabricated multicore fiber laser device can in principle be a single fiber chain that is only ~10 cm in length, aligning-free in operation, and robust against environmental disturbance. Keywords: fiber laser, multicore fiber, phase-locked oper ation, Talbot imaging, multimode interference 1. INTRODUCTION Multicore fiber (MCF) with doped core array has been recen tly developed and it brings a promising solution to power-scalable fiber lasers of short length.