%0 Journal Article %T Photonic crystal fiber Mach-Zehnder interferometer with microholes ablated by a femtosecond laser for refractive index sensing<br>Photonic crystal fiber Mach-Zehnder interferometer with microholes ablated by a femtosecond laser for refractive index sensing %A 吴鸿宾 %A 赵龙江 %A 王鹏 %A 曹志涛 %J 北京理工大学学报（自然科学中文版) %D 2016 %R 10.15918/j.jbit1004-0579.201625.0112 %X A new structure of the photonic crystal fiber (PCF) based Mach-Zednder interferometer (MZI) is fabricated and presented. The structure has microholes ablated by a femtosecond laser. The fringe visibility can be enhanced more than 10.dB compared with the interferometer without a microhole. The interferometer is characterized by sodium chloride solutions for refractive index (RI) sensing. The RI sensitivities are greatly increased by the hole fabrication since it directly changes the cladding modes of the PCF. For the interferometer sensor with two holes, the RI sensitivity is 157.74 nm/RIU, which is 5.times than that of the sensor without a microhole. Microholes ablation with a femtosecond laser on PCF can increase the sensor's sensitivity dramatically. Femtosecond laser has a wide application prospect in the field of performance improvement of the sensors.<br>A new structure of the photonic crystal fiber (PCF) based Mach-Zednder interferometer (MZI) is fabricated and presented. The structure has microholes ablated by a femtosecond laser. The fringe visibility can be enhanced more than 10.dB compared with the interferometer without a microhole. The interferometer is characterized by sodium chloride solutions for refractive index (RI) sensing. The RI sensitivities are greatly increased by the hole fabrication since it directly changes the cladding modes of the PCF. For the interferometer sensor with two holes, the RI sensitivity is 157.74 nm/RIU, which is 5.times than that of the sensor without a microhole. Microholes ablation with a femtosecond laser on PCF can increase the sensor's sensitivity dramatically. Femtosecond laser has a wide application prospect in the field of performance improvement of the sensors. %K photonic crystal fiber (PCF) sensor fs laser fabrication refractive index sensing< %K br> %K photonic crystal fiber (PCF) sensor fs laser fabrication refractive index sensing %U http://journal.bit.edu.cn/yw/bjlgyw/ch/reader/view_abstract.aspx?file_no=20160112&flag=1