Cai Dawei, Xie Yu, Wang Pan, Zhang Lei, Guo Xin, Tong Limin
Opt Lett. 2020 Nov 15;45(22):6114-6117. doi: 10.1364/OL.403893.
We report mid-infrared (mid-IR) Bragg gratings fabricated on sub-wavelength-diameter chalcogenide glass (ChG) microfibers. ChG microfibers with diameters around 3 µm are tapered drawn from glass fibers, and the mid-IR microfiber Bragg gratings (mFBGs) are inscribed on microfibers using interference patterns of near bandgap light at a 532 nm wavelength. At a wavelength of about 4.5 µm, the mFBG has an extinction ratio of 15 dB and a positive photo-induced refractive index change of 2×10. The dependence of the grating formation on accumulated influence of exposure power density and time is investigated. The mid-IR mFBGs demonstrated here may be used as building blocks for micro-photonic circuits or devices in the mid-IR spectral range.
我们报道了在亚波长直径硫系玻璃（ChG）微纤维上制备的中红外（mid-IR）布拉格光栅。直径约为3 µm的ChG微纤维是从玻璃纤维拉制而成的锥形纤维，并且使用波长为532 nm的近带隙光的干涉图案在微纤维上写入中红外微纤维布拉格光栅（mFBG）。在约4.5 µm的波长处，mFBG的消光比为15 dB，光致折射率正变化为2×10 。研究了光栅形成对曝光功率密度和时间累积影响的依赖性。这里展示的中红外mFBG可用作中红外光谱范围内微光电器件或设备的构建模块。
