Electrically tunable polarization‐independent visible transmission guided‐mode resonance filter based on polymer‐dispersed liquid crystals

Abstract

A tunable polarization-independent narrowband guidedmode resonance filter (GMRF), consisting of a 2D subwavelength aluminum grating and a polymer-dispersed liquid crystal (PDLC) layer is demonstrated. By taking advantage of 2D structural phase matching, the guided mode resonance occurs under both transverse electric and magnetic guided modes, we obtained polarizationindependent bandpass filtering without loss of polarization, as verified via finite-difference time-domain simulations. Meanwhile, we use PDLC as a property adjustable material, when the orientation of the PDLC was controlled with an applied voltage, the transform mode of the incident light changed, which enabled easy refractive index tunability. A finite element method was used to design and characterize a tunable GMRF with a transmission resonance wavelength that can be shifted from 492.31 to 505.94 nm, based on the PDLC refraction. The relationship between resonance wavelength and the PDLC refractive index exhibits a linear curve, the shape and peak of the resonance transmission curve is stable during adjustments. With the design of this structure parameter, the GMRF transmission efficiency was over 82% in the visible band.

Dual‐channel glucose concentration sensor based on coupled cross‐stacked gratings

“…Based on Table 1, the two figures in Figure 4 (A-B) were drawn to show the FWHM for glucose concentration and n a values, respectively. It is noted that the two figures have the same trend due to a linear relationship between glucose concentration and n a values, according to Equation (5). We can see that there is a monotonic linear change between concentration of glucose and FWHM for the second channel.…”

“…Guided-mode resonance (GMR) wavelength relies on the surrounded refractive index (RI), for which the GMR-based device can be engineered as RI sensor with high performance due to its extreme narrow linewidth and high sensitivity to surrounding analytes. [1][2][3][4] When GMR phenomenon occurs, [5][6][7] the diffraction orders excite a waveguide mode that couples out and interferes with the zeroth order mode to form resonant peaks under a resonance condition. 8,9 For RI biosensor, classical designs based on a single-channel biosensor could make it difficult for the analyte to reduce the nonsystematic errors under the environment disturbance.…”

Handheld Biosensor System Based on a Gradient Grating Period Guided-Mode Resonance Device

“…GMR sensors have undergone thorough exploration since the late 1980s [15][16][17]. Ongoing research efforts persist in investigating novel designs to enhance sensitivity, quality, or FOM [10,[18][19][20][21][22]. Additionally, GMR sensors continue to find implementation in emerging biosensing applications [23][24][25][26].…”

Ultra-Narrowband High-Transmissivity Guided-Mode Resonance Filter Based on Dual Dielectric Film Structure and High Refractive Index Waveguide Layer

“…Guangyu Sun et al presented a tunable polarization-independent narrowband GMR filter that employed a 2D subwavelength aluminum grating in conjunction with a polymer-dispersed liquid crystal layer. Although the transmittance reached 82.5%, the FWHM remained as high as 15 nm [31]. Xiangyu Ma et al designed a filter with periodic nanostructures and dielectric multilayers integrated on a silicon substrate.…”