Interferometric vs wavelength selective optical fiber sensors for cryogenic temperature measurements

In this work, a preliminary study of the behavior of two different interferometric fiber optic sensors and two different wavelength selective fiber optic sensors is performed. A photonic cristal fiber Fabry-Pérot interferometer, a Sagnac interferometer, a commercial fiber Bragg grating (FBG) and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser are analyzed. A comparison of their sensitivities and resolutions is carried out to analyze their performance as sensors for cryogenic temperatures, taking into account their advantages and drawbacks.Financial support from the Spanish Comisión Interministerial de Ciencia y Tecnología within projects TEC2013-47264-C2-2-R and TEC2016-76021-C2-1-R and the FEDER funds are acknowledged