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In this study, WO3/Ag/W/WO3 (WAWW) films were deposited at room temperature on a B270 glass substrate from W and Ag targets using a radiofrequency magnetron reactive sputtering system. The influence of the thin tungsten interlayer on the electrical and optical properties of the WAWW layer structure was investigated through ellipsometry, a four-point probe and a spectrophotometer. It was determined that the thin tungsten interlayer effectively prevented the oxidation of the silver film. The WAWW film had a dielectric-metal-dielectric (DMD) layered structure with good electrical conductivity and high visible transmittance. The tungsten layer was no more than 2-nm thick. The sheet resistance and luminous transmittance of the WO3(29.5 nm)/Ag(14.2 nm)/W(2 nm)/WO3(68.6 nm) film were 4.64 Ω/sq and 65.4 %, respectively. Based on the WAWW four-layer structure, stacked WO3(29.5 nm)/Ag(14.2 nm)/W(2 nm)/WO3(68.6 nm)/Ag(16.9 nm)/W(2 nm)/WO3(30.4 nm) seven-layer structures deposited on B270 glass substrates were used for both ITO-free electrochromic and hot mirror applications. The visible (400–700 nm) and NIR (700–1200 nm) transmittance values of the bleached WAWW seven-layer structure were 71.5 % and 9.9 %, respectively. The visible transmittance of the colored WAWW seven-layer structure was 23.6 %. Finally, the bi-layer WAWW films were used to obtain an ITO-free WAWW seven-layer structure with a good electrochromic and optical performance.

Guided-mode resonance (GMR) gratings have emerged as a promising sensing technology, with a growing number of applications in diverse fields. This study aimed to identify the optimal design parameters of a simple-to-fabricate and high-performance one-dimensional GMR grating. The structural parameters of the GMR grating were optimized, and a high-refractive-index thin film was simulated on the grating surface, resulting in efficient confinement of the electric field energy within the waveguide. Numerical simulations demonstrated that the optimized GMR grating exhibited remarkable sensitivity (252 nm/RIU) and an extremely narrow full width at half maximum (2 × 10−4 nm), resulting in an ultra-high figure of merit (839,666) at an incident angle of 50°. This performance is several orders of magnitude higher than that of conventional GMR sensors. To broaden the scope of the study and to make it more relevant to practical applications, simulations were also conducted at incident angles of 60° and 70°. This holistic approach sought to develop a comprehensive understanding of the performance of the GMR-based sensor under diverse operational conditions.