A compact singlemode-photonic crystal fibre-singlemode fibre tip (SPST) refractive index sensor is demonstrated in this paper. A CO2 laser cleaving is exploited to provide a clean-cut fibre tip which is then coated by a layer of gold to increase reflection. An average sensitivity of 39.1 nm/RIU and a resolvable index change of 2.56×10-4 are obtained experimentally with a ~3.2 µm diameter SPST. Because of its compactness, ease of fabrication, linear response, high sensitivity, easy connectivity to other fibreized optical components and low cost, this refractometer could find various applications in chemical and biological sensing.

Date Published: 2 June 2014
PDF: 4 pages
Proc. SPIE 9157, 23rd International Conference on Optical Fibre Sensors, 91578F (2 June 2014); doi: 10.1117/12.2059596

Published in SPIE Proceedings Vol. 9157:
23rd International Conference on Optical Fibre Sensors
José M. López-Higuera; Julian D. C. Jones; Manuel López-Amo; José Luis Santos, Editor(s)