Tunable kHz distributed feedback fiber laser enabled by glass additive-manufacturing

TL;DR

This paper demonstrates a tunable distributed feedback fiber laser made from Er-doped silica fiber fabricated via laser-powder-deposition additive manufacturing, achieving narrow linewidth and high efficiency, opening new avenues for rapid fiber device production.

Contribution

It introduces a novel use of laser-powder-deposition additive manufacturing for fabricating Er-doped silica fibers used in DFFLs, enabling rapid, customizable fiber laser production.

Findings

Achieved milliwatt-level narrow linewidth lasing (<704 kHz).

Backward slope efficiency reached 24% at 976 nm pumping.

Showcased the potential of additive manufacturing for advanced fiber laser fabrication.

Abstract

techniques can be considered as an attractive alternative to the often-cumbersome traditional manufacturing routes. With the use of high-power lasers, localized hot zones that are necessary for glass making can be obtained rapidly. For instance, Laser-Powder-Deposition enables rapid fabrication of short, high gain fibers used in e.g., distributed feedback fiber lasers (DFFL). DFFLs offer sought after performance suitable for a broad range of applications in modern photonics i.e., superior stability and narrower, single-frequency linewidth compared to conventional fiber lasers. Tunable, narrow laser sources with output in eye-safe spectrum are desired for sensing, signal multiplexing, LIDAR systems, quantum applications etc. In this work we present DFFL obtained using Laser-Powder-Deposition made Er-doped silica fiber. Milliwatt level, narrow line lasing (< 704 kHz, equipment limited) was obtained using a phaseshifted grating written in 16 mm long fiber. The backward slope efficiency was as high as 24% when pumping at 976 nm. The results presented in this work showcase new possibilities in fiber fabrication that were unlocked through laser-assisted additive manufacturing. This fiber laser sets the stage for the future of rapid fabrication of advanced fiber devices through unconventional manufacturing routes.