Ultra-Wideband High-Efficiency Solar Absorber and Thermal Emitter Based on Semiconductor InAs Microstructures

Abstract

Since the use of chemical fuels is permanently damaging the environment, the need for new energy sources is urgent for mankind. Given that solar energy is a clean and sustainable energy source, this study investigates and proposes a six-layer composite ultra-wideband high-efficiency solar absorber with an annular microstructure. It achieves this by using a combination of the properties of metamaterials and the quantum confinement effects of semiconductor materials. The substrate is W–Ti–Al2O3, and the microstructure is an annular InAs-square InAs film–Ti film combination. We used Lumerical Solutions’ FDTD solution program to simulate the absorber and calculate the model’s absorption, field distribution, and thermal radiation efficiency (when it is used as a thermal emitter), and further explored the physical mechanism of the model’s ultra-broadband absorption. Our model has an average absorption of 95.80% in the 283–3615 nm band, 95.66% in the 280–4000 nm band, and a weighted average absorption efficiency of 95.78% under AM1.5 illumination. Meanwhile, the reflectance of the model in the 5586–20,000 nm band is all higher than 80%, with an average reflectance of 94.52%, which has a good thermal infrared suppression performance. It is 95.42% under thermal radiation at 1000 K. It has outstanding performance when employed as a thermal emitter as well. Additionally, simulation results show that the absorber has good polarization and incidence angle insensitivity. The model may be applied to photodetection, thermophotovoltaics, bio-detection, imaging, thermal ion emission, and solar water evaporation for water purification.

Ultra-High-Sensitivity and -Stability Thin-Film Heat Flux Sensor Based on Transverse Thermoelectric Effect

“…Only (001) crystal plane diffraction peaks of the YBa 2 Cu 3 O 7-δ film appear, except for the LAO (001) substrate diffraction peak. This indicates that the film is single-phase and strictly (001) oriented, i.e., stacked along the c-axis between the film faces and epitaxially along the c-axis of the substrate [38][39][40]. The relatively sharp diffraction peaks of both the substrate and the film are a positive indication of good crystalline quality.…”

Terahertz absorber based on vanadium dioxide with high sensitivity and switching capability between ultra-wideband and ultra-narrowband

“…1(a) shows the three-dimensional array stereo view of the device, which mainly consists of a three-layer structure, with the Si material (refractive index n 1 = 3.3) and the phase change material vanadium dioxide in the top layer, SiO 2 (refractive index n 2 = 1.45) in the middle layer, and the noble metal gold (electrical conductivity σ au = 4.561 × 10 7 S m −1 ) in the bottom layer. 28,29 For a clearer view, the structure of a single resonant cell is shown in Fig. 1(b), the thicknesses of Si, VO 2 , SiO 2 , and Au are 10 μm, 0.1 μm, 8 μm, and 2 μm, respectively.…”

Switchable asymmetric transmission with broadband polarization conversion in vanadium dioxide-assisted terahertz metamaterials

“…To achieve dynamic control over the functionality of MMs, a variety of different schemes have been suggested by integrating active media in MM systems, such as superconductors, 18 semiconductors, 19,20 two-dimensional materials, 21–23 liquid crystals, 24–26 microelectromechanical systems, 27 and so on. As an alternative active material, phase-change materials have attracted great interest due to their direct control through external fields.…”