Ultrahigh-sensitivity temperature fiber sensor based on multimode interference

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Susana Silva (Author) FCUP; Edwin G. P. Pachon (Author) Other; Marcos A. R. Franco (Author) Other; Juliano G. Hayashi (Author) Other; F. Xavier Malcata (Author) FEUP; Orlando Frazão (Author) Other; Pedro Jorge (Author) Other; Cristiano M. B. Cordeiro (Author) Other

Journal

Title: Applied Optics

Vol. 51 No. 16

Pages: 3236-3242

ISSN: 1559-128X

Publisher: Optical Society of America

Indexing

ISI Web of Knowledge - 108 Citations

ISI Web of Science

Scopus - 128 Citations

Scientific classification

FOS: Engineering and technology

Other information

Authenticus ID: P-002-9A3

DOI: 10.1364/ao.51.003236

Abstract (EN): The proposed sensing device relies on the self-imaging effect that occurs in a pure silica multimode fiber (coreless MMF) section of a single-mode-multimode-single-mode (SMS)-based fiber structure. The influence of the coreless-MMF diameter on the external refractive index (RI) variation permitted the sensing head with the lowest MMF diameter (i.e., 55 mu m) to exhibit the maximum sensitivity (2800 nm/RIU). This approach also implied an ultrahigh sensitivity of this fiber device to temperature variations in the liquid RI of 1.43: a maximum sensitivity of -1880 pm/degrees C was indeed attained. Therefore, the results produced were over 100-fold those of the typical value of approximately 13 pm/degrees C achieved in air using a similar device. Numerical analysis of an evanescent wave absorption sensor was performed, in order to extend the range of liquids with a detectable RI to above 1.43. The suggested model is an SMS fiber device where a polymer coating, with an RI as low as 1.3, is deposited over the coreless MMF; numerical results are presented pertaining to several polymer thicknesses in terms of external RI variation. (C) 2012 Optical Society of America

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7