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Electron-spin to photon-polarisation conversion is a promising technology for achieving free-space or fibre coupled quantum transfer. Here, the authors demonstrate acoustically-driven single photons from single electrons, without the need for self-assembled quantum dots, using a SAW-driven lateral n-i-p junction.

The electrical and optical properties of semiconducting transition metal dichalcogenides (TMDs) can be tuned by controlling their composition and the number of layers they have. Among various TMDs, the monolayer WSe2 has a direct bandgap of 1.65 eV and exhibits p-type or bipolar behavior, depending on the type of contact metal. Despite these promising properties, a lack of efficient large-area production methods for high-quality, uniform WSe2 hinders its practical device applications. Various methods have been investigated for the synthesis of large-area monolayer WSe2, but the difficulty of precisely controlling solid-state TMD precursors (WO3, MoO3, Se, and S powders) is a major obstacle to the synthesis of uniform TMD layers. In this work, we outline our success in growing large-area, high-quality, monolayered WSe2 by utilizing methane (CH4) gas with precisely controlled pressure as a promoter. When compared to the catalytic growth of monolayered WSe2 without a gas-phase promoter, the catalytic growth of the monolayered WSe2 with a CH4 promoter reduced the nucleation density to 1/1000 and increased the grain size of monolayer WSe2 up to 100 μm. The significant improvement in the optical properties of the resulting WSe2 indicates that CH4 is a suitable candidate as a promoter for the synthesis of TMD materials, because it allows accurate gas control.

This study was carried out to test the antimicrobial activities of nano metal hybrid materials produced by plasma technologies (radio frequency–thermal plasma system and direct current sputtering system) against microbes isolated from cucurbit (watermelon, pumpkin, and gourd) seeds. Eight different nano metal hybrid materials and four carriers were tested against five different fungal and ten different bacterial isolates in vitro. Among the tested nano metal hybrid material, Brass/CaCO3 (1,000 ppm) exhibited 100% antimicrobial effect against all the five tested fungi. However, nano metal hybrid material Brass/CaCO3 (1,000 ppm) inhibited only four bacterial isolates, Weissella sp., Rhodotorula mucilaginosa, Burkholderia sp., and Enterococcus sp. at 100% level, and did not inhibited other six bacterial isolates. Nano metal hybrid material graphite-nickel (GNi) showed 100% inhibition rate against Rhizopus stolonifer and 52.94–71.76% inhibition rate against four different fungal isolates. Nano metal hybrid material G-Ni did not show any inhibition effects against tested ten bacterial isolates. In summary, among the tested eight different nano metal hybrid materials and four carriers, Brass/CaCO3 showed inhibition effects against five fungal isolates and four bacterial isolates, and G-Ni showed variable inhibition effects (52.94–100%) against five fungal isolates and did not show any inhibition effects against all the bacterial isolates.

The article presents a study that focuses on layer-engineered large-area exfoliation of graphene. It mentions that how layer-engineered exfoliation technique can pave the way for the development of a manufacturing-scale process for graphene and other two-dimensional materials in electronics and optoelectronics.