Fiber-optic refractive-index sensors based on transmissive and reflective thin-core fiber modal interferometers

Tian Hao Xia, Aping Zhang, Bobo Gu, Jing Jing Zhu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

96 Citations (Scopus)


We present a new fiber-optic refractive-index sensor based on a fiber modal interferometer constituted by a thin-core optical fiber, whose cut-off wavelength is around three times shorter than normal single-mode fiber. In such a core diameter mismatching structure, the high-order cladding modes are efficiently excited and interfere with the core mode to form a high extinction-ratio filter (>30 dB). Both transmissive and reflective thin-core fiber modal interferometers are experimentally demonstrated, and show a high sensitivity to a small change of external refractive-index (>100 nm/R.I.U.), but a low sensitivity to the change of temperature (<0.015 nm/°C). Such a fiber device possesses an extremely simple structure, but excellent refractive-index sensing properties, and thus is an ideal candidate for fiber-optic biochemical sensing applications.
Original languageEnglish
Pages (from-to)2136-2139
Number of pages4
JournalOptics Communications
Issue number10
Publication statusPublished - 15 May 2010
Externally publishedYes


  • Fiber-optic interferometer
  • Optical fiber sensor
  • Refractive-index sensor

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Physical and Theoretical Chemistry
  • Electrical and Electronic Engineering

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