The renaissance and bright future of fibre lasers

TLDR

Early rare‑earth‑doped fibre lasers produced only milliwatts, but recent advances have pushed kilowatt‑level, diffraction‑limited output. This review examines the drivers behind fibre laser power scaling. The authors highlight how photonic crystal fibres enable further power scaling and open new performance regimes for solid‑state lasers.

Abstract

The first rare-earth-doped fibre lasers were operated in the early 1960s and produced a few milliwatts at a wavelength around 1 µm. For the next several decades, fibre lasers were little more than a low-power laboratory curiosity. Recently, however, fibre lasers have entered the realm of kilowatt powers with diffraction-limited beam quality. In this paper we review the reasons for this power evolution. Beyond this, we will discuss how the next generation of fibres, so-called photonic crystal fibres, enable upward power scaling and therefore open up the avenue to new performance levels of solid-state lasers.