Author(s): Yang, Y (Yang, Ying); Liu, YY (Liu, Yuanyuan); Yang, S (Yang, Shuo); Wu, YQ (Wu, Yongqin); Tian, HP (Tian, Huiping)

Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Volume: 38 Issue: 6 Pages: 1927-1933 DOI: 10.1364/JOSAB.423465 Published: JUN 1 2021

Abstract: In this work, the silicon-nitride-based double-layered photonic crystal slab (DPCS) operating on guided-mode resonance (GMR) is demonstrated to realize a high-sensitivity sensor. By applying the three-dimensional finite-difference time-domain (3D-FDTD) analysis method, the relationships between Q-factor and slab thickness, hole radius, and space distance are extensively explored. The highest Q-factor of 7605 has been obtained for the optimized structure. Through detecting the resonant peak shifts when the DPCS sensor is immersed in different liquids, we realize an ultrahigh sensitivity up to 937.64 nm/refractive index unit (RIU). On the other hand, particle detection is simulated by the above-mentioned sensor, and the explanations of different resonant shifts versus different trapped positions are sophisticatedly elucidated. Furthermore, the effect of the vertical alignment deviation (lattice displacement) of the two photonic crystal slabs (PCSs) on the Q-factor and transmittance is discussed in detail. The investigations show that the DPCS sensor allows an alignment deviation of similar to 40 nm, which exhibits excellent fabrication error robustness. (C) 2021 Optical Society of America

Accession Number: WOS:000658147500021

ISSN: 0740-3224

eISSN: 1520-8540

Full Text: https://www.osapublishing.org/josab/fulltext.cfm?uri=josab-38-6-1927&id=451305