Single-mode Fiber-loop Refractometer based on resonant modal couplings

LONDERO, CAROLINA; DELGADO PINAR, MARTINA; CUADRADO LABORDE, CHRISTIAN; ANDRES BOU, MIGUEL

Madrid

Congreso; XII Reunión Española de Optoelectrónica, OPTOEL?21; 2021

In the present work, a fiber-loop refractometer based on resonant modal couplings was fabricated and characterized in detail. The dependence of resonant wavelengths of thecouplings with the loop diameter was studied, as well as the effect of temperature. Theperformance of the optical response in solutions with refractive indices in the range[1.33 , 1.37] of two particular loops of diameters 10.5 mm and 12 mm was measured, andthe sensitivity and limit of detection of these refractometers were determined. Resultsindicate that these easy-fabrication fiber-loops show good sensitivities: the 12 mm loopshows sensitivity values of 327.69 and 378.38 nm/RIU for notches located at the vicinities of 1515 nm. The correspondent detection limit is 5·10-4 RIU. The performanceof the fiber-loop makes of it a promising device for biosensing applications.