Articles
Publication Date: 2023
Journal of Optics (United Kingdom) (20408986)25(8)
In this paper, we propose a reconfigurable two-dimensional photonic crystal (PC) made from a new ultralow loss phase change material for detecting and imaging applications of surface-enhanced Raman scattering (SERS). The proposed all-dielectric structure is composed of identical holes periodically distributed on Sb2S3 as a substrate, tuned by optical pumping. The proposed PC is investigated using full-wave simulation of the CST with the finite-difference frequency domain method over a wide bandwidth of optical wavelengths. In this study, compensation for the error of the Fano resonance wavelength due to the fabrication process is realized through tuning optical pumping applied to the configuration. Also, the numerical results show the designed PC supports two high-quality Fano resonance modes, leading to uniform and high field enhancement with a SERS enhancement factor of 1.23 × 1012, which is significant for the application of SERS enhancement. © 2023 The Author(s). Published by IOP Publishing Ltd
Publication Date: 2022
Journal of the Optical Society of America B: Optical Physics (07403224)39(1)pp. 145-154
Integrating plasmonic metasurfaces with transparent conductive oxide (TCO) materials provides a new, to the best of our knowledge, opportunity to dynamically manipulate all degrees of freedom of light beams. Applying external stimuli to TCOs changes the plasmonic response of the nanostructure as a result of establishing an inhomogeneous optical property with deeply subwavelength films of epsilon-near-zero media, which is a challenge for better theoretical understanding of the dynamical tuning functionality. In this paper, we propose a dynamically reconfigurable reflective metasurface with the capability of electrical manipulation of the polarization state of near-infrared light. The structure behavior is investigated by numerical analysis and described based on the coupled-mode theory concept using the parameters of resonance wavelength, absorption, and radiation quality factors, altered by an external voltage. Variation of the applied bias voltage from −0.7 to 4.2 V for p-polarized light leads to a wide range of absorption quality factors from 43 to two. This change causes a dramatic decrease in the equivalent surface impedance of the metasurface in the ratio 4.9:0.2, which may pave the way to tailor polarization-manipulating functions such as circular-to-linear polarization conversion and cross-polarization conversion. © 2021 Optical Society of America
