Liu Shuhui, Wang Ying, Hou Maoxiang, Guo Jiangtao, Li Zhihua, Lu Peixiang
Opt Express. 2013 Dec 16;21(25):31690-7. doi: 10.1364/OE.21.031690.
Mechanism and sensing applications of antiresonant reflecting guidance in an alcohol-filled simplified hollow-core (SHC) photonic crystal fiber (PCF) are demonstrated. By filling one air hole in the air cladding of the PCF with alcohol, anti-resonant reflecting guidance of light can be achieved and energy leakage of the core modes can be induced at resonant wavelengths of the Fabry-Pérot (F-P) resonator formed by the alcohol-filled layer combined with the silica cladding in the cross-section of the PCF. The proposed structure exhibits periodic lossy dips in the transmission spectrum, of which the visibilities are sensitive to the refractive index of surrounding medium due to the reflectivity variation of the F-P resonator. Water level sensing is experimentally realized with this principle and the lossy dip exhibits a linear decrease against water level with a sensitivity of 1.1 dB/mm. The sensor is also sensitive to environmental temperature and a temperature sensitivity of -0.48 nm/°C is obtained between room temperature and 60 °C.
阐述了在充满酒精的简化空心（SHC）光子晶体光纤（PCF）中，反谐振反射导光的机理及其传感应用。通过在PCF空气包层的一个气孔中填充酒精，可实现光的反谐振反射导光，并在由填充酒精层与PCF横截面中的二氧化硅包层形成的法布里-珀罗（F-P）谐振器的谐振波长处，引发纤芯模式的能量泄漏。所提出的结构在传输光谱中呈现出周期性的损耗凹陷，由于F-P谐振器的反射率变化，其可见度对周围介质的折射率敏感。利用这一原理通过实验实现了水位传感，损耗凹陷随水位呈线性下降，灵敏度为1.1 dB/mm。该传感器对环境温度也很敏感，在室温至60°C之间获得的温度灵敏度为-0.48 nm/°C。
