Negative Curvature Hollow Core Fiber Based All-Fiber Interferometer and Its Sensing Applications to Temperature and Strain
Dejun Liu,
Wei Li,
Qiang Wu,
Haoyu Zhao,
Fengzi Ling,
Ke Tian,
Changyu Shen,
Fangfang Wei,
Wei Han,
Gerald Farrell,
Yuliya Semenova,
Pengfei Wang
Affiliations
Dejun Liu
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Wei Li
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Qiang Wu
Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
Haoyu Zhao
Technical Center, Sichuan Changhong Electric Co., Ltd., Mianyang 621000, China
Fengzi Ling
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Ke Tian
Key Lab of In-fiber Integrated Optics, Ministry Education of China, Harbin Engineering University, Harbin 150001, China
Changyu Shen
Institute of Optoelectronic Technology, China Jiliang University, Hangzhou 310018, China
Fangfang Wei
Photonics Research Centre, Technological University Dublin, Kevin Street, Dublin 8, Ireland
Wei Han
Photonics Research Centre, Technological University Dublin, Kevin Street, Dublin 8, Ireland
Gerald Farrell
Photonics Research Centre, Technological University Dublin, Kevin Street, Dublin 8, Ireland
Yuliya Semenova
Photonics Research Centre, Technological University Dublin, Kevin Street, Dublin 8, Ireland
Pengfei Wang
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Negative curvature hollow core fiber (NCHCF) is a promising candidate for sensing applications; however, research on NCHCF based fiber sensors starts only in the recent two years. In this work, an all-fiber interferometer based on an NCHCF structure is proposed for the first time. The interferometer was fabricated by simple fusion splicing of a short section of an NCHCF between two singlemode fibers (SMFs). Both simulation and experimental results show that multiple modes and modal interferences are excited within the NCHCF structure. Periodic transmission dips with high spectral extinction ratio (up to 30 dB) and wide free spectral range (FSR) are produced, which is mainly introduced by the modes coupling between HE11 and HE12. A small portion of light guiding by means of Anti-resonant reflecting optical waveguide (ARROW) mechanism is also observed. The transmission dips, resulting from multimode interferences (MMI) and ARROW effect have a big difference in sensitivities to strain and temperature, thus making it possible to monitor these two parameters with a single sensor head by using a characteristic matrix approach. In addition, the proposed sensor structure is experimentally proven to have a good reproducibility.
