Selective doping of Ni2+ in highly transparent glass-ceramics containing nano-spinels ZnGa2O4 and Zn1+x Ga2−2x Ge x O4 for broadband near-infrared fiber amplifiers

• Published in: Scientific reports Vol. 7; no. 1; pp. 1 - 8
• Main Authors: Gao, Zhigang, Liu, Yinyao, Ren, Jing, Fang, Zaijin, Lu, Xiaosong, Lewis, Elfed, Farrell, Gerald, Yang, Jun, Wang, Pengfei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 11.05.2017; Nature Portfolio
• Subjects: Ceramics; Crystal structure; Crystals; I.R. radiation; Luminescence; Nanocrystals; Temperature tolerance
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-01676-6

Abstract Selective doping of Ni 2+ in octahedral sites provided by nanocrystals embedded in glass-ceramics (GCs) is crucial to the enhancement of broadband near-infrared (NIR) emission. In this work, a NIR emission with a full-width-at-half-maximum (FWHM) of 288 nm is first reported from ZnGa 2 O 4 : Ni 2+ nano-spinels embedded GCs with excellent transparency. A comparison is made of the NIR luminescence properties of Ni 2+ doped GCs containing ZnGa 2 O 4 , germanium-substituted ZnGa 2 O 4 nano-spinels (Zn 1+ x Ga 2−2 x Ge x O 4 ), and Zn 2 GeO 4 /Li 2 Ge 4 O 9 composite nanocrystals that are free of Ga 3+ . The results show that ZnGa 2 O 4 : Ni 2+ GCs exhibit a significantly enhanced NIR emission. The incorporation of the nucleating agent TiO 2 is favored in terms of the increased luminescence intensity and prolonged lifetime. The possible causes for the enhancement effect are identified from the crystal structure/defects viewpoint. The newly developed GCs incorporate good reproducibility to allow for a tolerance of thermal treatment temperature and hence hold great potential of fiberization via the recently proposed “melt-in-tube” method. They can be considered as promising candidates for broadband fiber amplifiers.