Taper-fused side pump combiner for all-fiber lasers and amplifiers: A review

A taper-fused side pump technique, which is based on the direct fusion-splicing of one or several tapered pump fibers and a double-clad signal fiber, is a potential side pump technique for high power all-fiber lasers and amplifiers because of its high pump/signal transmission efficiency and the capability of handling high pump power up to kW-class. During the past several years, we have observed tremendous research efforts in the development of side pump combiner. In this paper, we report on the recent progress of taper-fused side pump combiner for all-fiber lasers and amplifiers. We will present the principles and fabrication process of this combiner, summarize its current performance and new applications, analyze the influence of design parameters on its performance, and for the first time discuss the challenges of further increasing the power handling capability of this technique.