title: Multibeam Interferometer Using a Photonic Crystal Fiber with Two Asymmetric Cores for Torsion, Strain and Temperature Sensing.
abstract: We present a fiber-optic multibeam Mach-Zehnder interferometer (m-MZI) for simultaneous multi-parameter measurement. The m-MZI is comprised of a section of photonic crystal fiber integrated with two independent cores of distinct construction and birefringence properties characterized for torsion, strain and temperature sensing. Due to the presence of small core geometry and use of a short fiber length, the sensing device demonstrates inter-modal interference in the small core alongside the dominant inter-core interference between the cores for each of the orthogonal polarizations. The output spectrum of the device is characterized by the three-beam interference model and is polarization-dependent. The two types of interferometers present in the fiber m-MZI exhibit distinct sensitivities to torsion, strain and temperature for different polarizations, and matrix coefficients allowing simultaneous measurement of the three sensing parameters are proposed in experiment.
authors.affiliation: Center for Safety Measurement, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea. knaeem@kriss.re.kr.
authors.forename: Khurram
authors.initials: K
authors.lastname: Naeem
authors.affiliation: Center for Safety Measurement, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea. ibkwon@kriss.re.kr.
authors.forename: Il-Bum
authors.initials: IB
authors.lastname: Kwon
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 61005, Korea. ychung@gist.ac.kr.
authors.forename: Youngjoo
authors.initials: Y
authors.lastname: Chung
keywords: asymmetric two-core PCF; high birefringence; multibeam interferometer; strain; temperature; torsion