Open AccessUltracompact gas-sensor based on a 2D photonic crystal waveguide incorporating with tapered microcavity
Author(s) -
Ahlam Harhouz,
Abdesselam Hocini,
Hadjira Tayoub
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1046/1/012001
Subject(s) - refractive index , photonic crystal , finite difference time domain method , materials science , optics , plane wave expansion , waveguide , hexagonal lattice , wavelength , resonator , optoelectronics , physics , antiferromagnetism , condensed matter physics
In this study, a new ultra compact gas-sensor, based on a 2D photonic crystal waveguide incorporating with tapered microcavity, is designed to detect small refractive index changes. The refractive index (RI) sensor is formed by a point-defect resonant cavity in the sandwiched waveguide on Si slab with triangular lattice. The properties of the sensor are simulated by using the plane wave expansion (PWE) method and the finite-difference time-domain (FDTD) algorithm. The transmission spectra of the sensor with different ambient refractive indices ranging from n = 1.0 to n = 1.01 are calculated. The calculation results show that a change in ambient refractive index of Δn=1×10 −4 is apparent. The proposed sensor achieves a sensitivity (Δλ/Δn) of 523.2 nm/RIU. It was found that the resonance wavelength is a linear function of the refractive index in under study range. The sensor is appropriate for detecting homogeneous media.