Mach-Zehnder Based on Large Knot Fiber Resonator for Refractive Index Measurement

• Type: Article in International Scientific Journal
• Date: 2016

Authors

Gomes, AD (Author) Other; Frazao, O (Author) FCUP

Journal

Title: IEEE Photonics Technology Letters

Vol. 28

Pages: 1279-1281

ISSN: 1041-1135

Publisher: IEEE

Indexing

ISI Web of Knowledge - 14 Citations

Scopus - 13 Citations

Other information

Authenticus ID: P-00K-9T6

DOI: 10.1109/lpt.2016.2538963

Abstract (EN): A Mach-Zehnder sensor based on a large knot fiber resonator with a diameter of a few millimeters is designed using a single long taper. The long taper of some centimeters is fabricated with a CO2 laser technique. In air, light cannot couple between adjacent sections in the knot, and no signal is observed. However, in liquid, light is less confined and there is coupling between adjacent sections of the knot, resulting in a phase difference and consequent interference. The Mach-Zehnder is formed by the two contact points in the knot. The refractive index sensing of liquid compounds is achieved by monitoring the wavelength shift of the spectra. A sensitivity of 642 +/- 29 nm/refractive index unit (RIU) is achieved for refractive index sensing in the range of 1.3735-1.428 with a resolution of 0.009 RIU. For temperature sensing, a sensitivity of -42 +/- 9 pm/degrees C is observed. A low influence of temperature in the refractive index change is observed: 6.5 x 10(-5) RIU/degrees C.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 3