Abstract

In this Letter, a theoretical analysis and design methodology of integrated long period gratings (LPGs) for refractometric applications are proposed. A detailed parametric analysis is applied to a LPG model based on two strip waveguides to highlight the main design variables and their effect on the refractometric performances, with focus on the spectral sensitivity and signature response. To illustrate the proposed methodology, four variants of the same LPG design are simulated with eigenmode expansion, displaying a wide range of sensitivities up to 300,000 nm/RIU with figures of merit (FOMs) as high as 8000.

© 2022 Optica Publishing Group

High-sensitivity integrated SiN rib-waveguide long period grating refractometer

Clement Deleau, Han Cheng Seat, Olivier Bernal, and Frederic Surre
Photon. Res. 10(2) 564-573 (2022)

Ultrasensitive refractometer based on helical long-period fiber grating near the dispersion turning point

Shen Liu, Min Zhou, Zhe Zhang, Zhongyuan Sun, Zhiyong Bai, and Yiping Wang
Opt. Lett. 47(10) 2602-2605 (2022)

Highly sensitive refractometer with a photonic-crystal-fiber long-period grating

Lars Rindorf and Ole Bang
Opt. Lett. 33(6) 563-565 (2008)

Distributed curvature sensing using long period fiber grating and machine learning numerical analysis

Clement Deleau, Han Cheng Seat, Olivier Bernal, and Frederic Surre
Opt. Lett. 48(19) 4941-4944 (2023)

Long-period gratings on lithium-niobate waveguides: phase-matching turning points for ultra-broadband mode conversion

Chenxu Lu, Wei Jin, and Kin Seng Chiang
Opt. Lett. 47(16) 3984-3987 (2022)