Search

A UV-NIR metamaterial absorber (MMA) based on a two-dimensional titanium grating that is sensitive to polarization is proposed. The absorber is composed of a two-dimensional titanium grating shaped as a four-edge platform, a one-dimensional SiO 2 grating, and an Au substrate. When the incident light is polarized in the X direction, the absorber achieves ultra-broadband absorption of 95.72 % in the range of 300–2400 nm. When the incident light is polarized in the Y direction, the absorber exhibits near-perfect ultra-narrowband absorption at 351 nm, and the Q factor and the sensitivity (S) of the narrowband absorption are 38.14 and 123.21 nm/RIU, respectively. The absorber also achieves polarization angle selective absorption at 400–2400 nm with an average extinction ratio of 25.73. Both the impedance matching theory and the energy distribution of the electromagnetic field explain the polarization-sensitive MMA well. The proposed absorber is resistant to changes in incidence angle and may be useful in polarization imaging, photoelectric detection, and optical sensors. [ABSTRACT FROM AUTHOR]

• C12E5 and Triton X-100 had better wetting effects than other surfactants. • The incubation rate of CN decreased with increasing C12E5 or Triton X-100 content. • C12E5 or Triton X-100 improved the beta-cyfluthrin 3% EW against CN. This study was conducted to investigate the wetting behavior of different surfactant solutions on the leaf surfaces of apple during the fruit formation stage. Five surfactants, including C 12 E 5 , Tween-20, Triton X-100, DTAB, and SDS were evaluated in this study. The contact angle, surface tension, adhesion tension, work of adhesion, and solid-liquid interface tension of droplets on the leaf surface were determined by the drop method. The results showed that the nonionic surfactants C 12 E 5 and Triton X-100 had better wetting effects than other surfactants. Moreover, when the concentration of C 12 E 5 and Triton X-100 was 1 × 10−3 mol/L, the leaves reached a completely wet state. Toxicity measurement showed that the incubation rate of Carposina niponensis eggs decreased graduall y with increasing content of C 12 E 5 or Triton X-100. Additionally, field efficacy analysis showed that adding C 12 E 5 or Triton X-100 significantly improved the beta-cyfluthrin 3% water emulsion (EW) against C. niponensis. These results indicate that the surfactants C 12 E 5 and Triton X-100 can significantly improve pesticide application, which will be helpful for reducing pesticide use and developing new pesticides. [ABSTRACT FROM AUTHOR]

The spin–valley transport is studied in a Fermi velocity-modulated monolayer WSe 2 magnetic superlattice. Based on these results, a scheme that can achieve an enhancing and switching spin–valley filter is proposed in the superlattice system. We find the Fermi velocity enhanced and switched spin-valley dependent conductance transport gaps by increasing the number of Fermi velocity barriers, which are verified by the transmission probabilities and Bloch theorem. When compared to a mono-periodic superlattice, the maximum spin ↓ and valley K′ polarized conductance in a well-constructed superlattice structure are greatly improved to a detectable degree. More importantly, the crucial bias voltage or exchange field can dynamically flip and control the valley polarized conductance, something that is not possible in a mono-periodic superlattice. Our findings indicate that a Fermi velocity modulated superlattice structure can be a great way to improve the spin-valley filtered polarizations of devices based on transition metal dichalcogenides. • A Fermi velocity combined with superlattice-modulated WSe 2 junction was proposed. • The spin ↓ and valley K′ polarized conductance is improved to a measurable amount. • These polarized conductance can be switched and tuned by bias voltage/exchange field. • These polarizations are supported by transmission probabilities and Bloch theorem. [ABSTRACT FROM AUTHOR]