High-power lasing at ∼900 nm in Nd<sup>3+</sup>-doped fiber: a direct coordination engineering approach to enhance fluorescence
Yinggang Chen, Zhiquan Lin, Hong‐Tao Sun, Yafei Wang, Hehe Dong, Meng Wang, Lei Zhang, Guoping Dong, Xiaofeng Liu, Fei Yu, Shikai Wang, Chunlei Yu, Lili Hu
Abstract
Lasers at ∼900nm have been of vital importance in various fields, including material processing, underwater communications, and strong-field physics. Although Nd 3+ -doped materials have been employed for the ∼900nm laser, the ∼900nm emission is in strong competition with the often more dominating ∼1060nm emission, which strongly limits the output power and applications. This paper proposes a direct coordination engineering approach, which introduces halogen to the nearest coordination of Nd 3+ in glass for increasing the bond covalency, leading to stronger emissions at ∼900nm than at ∼1060nm. Iodide-incorporated Nd 3+ -doped silica fibers show prevailing ∼900nm emission rarely observed in Nd 3+ -doped materials. Using the created fibers, a power (113.5 W) 50 times higher than the current record is accomplished based on an all-fiber structure. Our approach holds the potential for regulating the spectroscopic properties of other rare-earth-doped laser materials.