Lai Chien-Chih, Cheng Nai-Chia, Wang Cheng-Kai, Tjiu Jeng-Wei, Lin Ming-Yi, Huang Sheng-Yao
Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan.
Opt Express. 2013 Jun 17;21(12):14606-17. doi: 10.1364/OE.21.014606.
We propose and demonstrate a facile approach for ultraviolet-visible broadband generation from a sapphire crystal core-borosilicate glass cladding hybrid fiber using a laser-heated pedestal growth technique. Considerable formation of F- and F(2)-type color emitters is effectively facilitated by Ti(4+) ions and Al(3+) vacancies, retaining efficient luminescence and high crystallinity of the sapphire core. These color centers intensify the ultraviolet, blue, and green emissions at 370, 450, and 540 nm, whereas the 650-nm red emission is contributed by Cr(3+) in the octahedral sites of the corundum structure. Over 1-mW white light with an optical-to-optical efficiency of up to nearly 5% and 1931 Commission International de l'Eclairage chromaticity coordinate of (0.287, 0.333) is achieved under 325-nm excitation.
我们提出并演示了一种简便的方法，用于通过激光加热基座生长技术从蓝宝石晶体芯-硼硅酸盐玻璃包层混合光纤中产生紫外-可见宽带光。Ti(4+)离子和Al(3+)空位有效地促进了大量F型和F(2)型色心的形成，同时保持了蓝宝石芯的高效发光和高结晶度。这些色心增强了370、450和540 nm处的紫外、蓝光和绿光发射，而650 nm的红光发射则由刚玉结构八面体位置的Cr(3+)贡献。在325 nm激发下，实现了超过1 mW的白光，光-光效率高达近5%，国际照明委员会1931色度坐标为(0.287, 0.333)。
