title: Thermo-optic coefficient measurement of liquids based on simultaneous temperature and refractive index sensing capability of a two-mode fiber interferometric probe.
abstract: A fiber-optic interferometric probe based on a two-mode fiber (TMF) is proposed and demonstrated for measuring the thermo-optic coefficients (TOCs) of liquid samples. The proposed probe can be simply fabricated by fusion-splicing a short piece of TMF to a lead single mode fiber (SMF) with small lateral offset, which makes interference between LP(01) and LP(02) modes. The sensing responses of the probe to temperature and surrounding refractive index (SRI) have been experimentally investigated to show the capability of simultaneous measurements; the phase change of the reflection spectrum was related to temperature variation and the intensity change was to SRI variation. The data analysis is made not only in the spectral domain but in the Fourier domain also to effectively quantify the measurements. The TOCs of several liquid samples including water, ethanol, and acetone have been obtained with the proposed method.
authors.affiliation: School of Information and Communications, Gwangju Institute of Science and Technology, 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 500-712, South Korea.
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Seong Jun
authors.initials: SJ
authors.lastname: Park
authors.forename: Sie-Wook
authors.initials: SW
authors.lastname: Jeon
authors.forename: Seongmin
authors.initials: S
authors.lastname: Ju
authors.forename: Chang-Soo
authors.initials: CS
authors.lastname: Park
authors.forename: Won-Taek
authors.initials: WT
authors.lastname: Han
authors.forename: Byeong Ha
authors.initials: BH
authors.lastname: Lee
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D007368:Interferometry / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D012996:Solutions / Q000032:analysis* / Q000737:chemistry*; D013814:Thermal Conductivity; D013817:Thermography / Q000295:instrumentation*; D014159:Transducers
chemical_list: D012996:Solutions