Investigation of refractive index sensing based on Fano resonance in fiber Bragg grating ring resonators
Autori: Campanella C. E., De Leonardis F, Mastronardi L., Malara P., Gagliardi G., Passaro V. M. N.
Affiliazione autori: Dipartimento di Ingegneria Elettrica e dell’informazione, Politecnico di Bari, via Edoardo Orabona 4, 70125 Bari, Italy;
Istituto Nazionale di Ottica, Consiglio nazionale delle Ricerche, via Campi Flegrei 34, Comprensorio Olivetti 80078 Pozzuoli (Napoli) Italy
Abstract: In this paper we theoretically investigate a ring resonant cavity obtained by closing on itself a pi-shifted fiber Bragg grating, to be used for refractive index sensing applications. Differently from a conventional pi-shifted fiber Bragg grating, the spectral structure of this cavity is characterized by an asymmetric splitting doublet composed by a right side resonance having an asymmetric Fano profile and a left side resonance having a symmetric Lorentzian profile. The right side resonance shows a narrower and sharper peak than all the other kinds of resonance achievable with both conventional ring resonators and pi-shifted fiber Bragg gratings. A reduction of the resonant linewidth with respect to a conventional pi-shifted Fiber Bragg grating and a fiber ring resonator, having the same physical parameters, is theoretically proved, achieving up to five orders of magnitude improvement with respect to the usual ring resonator. Due to these resonance features, the pi-shifted Bragg grating ring resonator results suitable for RI sensing applications requiring extremely narrow resonances for high resolution measurements. In particular, by assuming a refractive index sensing to detect the presence of sugar in water, the sensor can show a theoretical resolution better than 10(-9) RIU. (C)2015 Optical Society of America
Giornale/Rivista: OPTICS EXPRESS
Volume: 23 (11) Da Pagina: 14301 A: 14313
Maggiori informazioni: This work has been partially supported by Politecnico di Bari under Fondo Ricerca di Ateneo (FRA) 2012 funding scheme.Parole chiavi: Bragg gratings; Fiber Bragg gratings; Fibers; Optical resonators; Resonance; Resonators, Asymmetric splitting; Fiber ring resonators; High-resolution measurements; In-fiber Bragg gratings; Orders of magnitude; Physical parameters; Refractive index sensing; Sensing applications; Refractive indexDOI: 10.1364/OE.23.014301Citazioni: 25dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2021-09-19Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui