title: Highly sensitive surface plasmon resonance sensor utilizing a long period grating with photosensitive cladding.
abstract: In this study, we propose and investigate a novel grating-assisted surface plasmon resonance (SPR) platform based on a silver coated long period fiber grating having a photosensitive cladding (C-LPFG). We show that the SPR mode is transited from the higher EH mode with an effective refractive index (ERI) close to that of the surrounding refractive index (SRI) and is highly sensitive to a change in the SRI. Compared with a conventional SPR sensor, a much higher sensitivity is obtained for the novel C-LPFG-based SPR sensor. The sensitivity can be further improved by reducing the fiber diameter. The numerical results show that the highest local sensitivity, which can be as high as ∼4900  nm/RIU, and the corresponding resolution of ∼2.04×10(-6)  RIU are achieved for the reduced silver coated C-LPFG sensor. Moreover, the Q-factor and the figure of merit exhibit better characteristics than those of the conventional LPFG-based SPR sensor. Our findings provide insight into the C-LPFG-based SPR platform being a potentially important area to explore for biochemical sensing.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.forename: Zhaogang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yanming
authors.initials: Y
authors.lastname: Zhou
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Zhong
authors.initials: Z
authors.lastname: Xie
mesh_terms: D003198:Computer Simulation; D009716:Numerical Analysis, Computer-Assisted; D055100:Optical Fibers; D055620:Optical Phenomena; D012031:Refractometry; D012834:Silver / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D012834:Silver