Open AccessHighly Sensitive Refractive Index Optical Fiber Sensors Fabricated by a Femtosecond Laser
Author(s) -
Jinpeng Yang,
Lan Jiang,
Sumei Wang,
Qianghua Chen,
Benye Li,
Hai Xiao
Publication year - 2011
Publication title -
ieee photonics journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.725
H-Index - 73
eISSN - 1943-0655
pISSN - 1943-0647
DOI - 10.1109/jphot.2011.2176535
Subject(s) - engineered materials, dielectrics and plasmas , photonics and electrooptics
Highly sensitive and robust refractive index (RI) fiber sensors are proposed, which are based on concatenating two micro air-cavities. The micro air-cavities embedded in the fiber along the core axis are fabricated by combining the techniques of femtosecond laser micromachining and arc fusion splicing. The full-width at half-maximum (FWHM) of an attenuation peak of a sensor in air is 0.048 nm, and the extinction ratio is ~ 15 dB. When the diameter of the cavity is slightly larger than the fiber core diameter, the sensor is highly sensitive to external RI changes. A high sensitivity of 172.4 nm/refractive index unit (RIU) around the RI range of 1.333-1.365 is achieved, which is about six times higher than long-period fiber grating (LPFG)-type and taper-type RI sensors in the same RI range.