Island nucleation and growth play an important role in thin-film growth. One quantity of particular interest is the exponent χ, which describes the dependence of the saturation island density N_{sat}∼(D_{h}/F)^{-χ} on the ratio D_{h}/F of the monomer hopping rate D_{h} to the deposition rate F. While standard rate equation (RE) theory predicts that χ=i/(i+2) (where i is the critical island size), more recently it has been predicted that in the presence of a strong barrier to the attachment of monomers to islands, a significantly larger value χ=2i/(i+3) may be observed.
View Article and Find Full Text PDFZnO nanoparticles (NPs) with a flower-like morphology, synthesized by an affordable colloidal route using an aqueous fungi extract of Ganoderma lucidum as a reducing agent and stabilizer, are investigated as SERS-substrate. Each "flower" has large effective surface that is preserved at packing particles into a dense film and thus exhibits an advantageous property for SERS and similar sensing applications. The mycoextract used in our low-cost and green synthesis as surface stabilizer allows subsequent deposition of metal NPs or layers.
View Article and Find Full Text PDFMetallic nanoparticles of different compositions have already found numerous applications in various branches of industry, agriculture, and medicine. Given the well-known antibacterial activity of Ag, silver nanoparticles (AgNPs) are constantly being investigated for their promising ability to fight antibiotic-resistant pathogens. A promising candidate for AgNPs biosynthesis is chili pepper Capsicum annuum, cultivated worldwide and known for accumulating significant amounts of active substances.
View Article and Find Full Text PDFDark matter elastic scattering off nuclei can result in the excitation and ionization of the recoiling atom through the so-called Migdal effect. The energy deposition from the ionization electron adds to the energy deposited by the recoiling nuclear system and allows for the detection of interactions of sub-GeV/c^{2} mass dark matter. We present new constraints for sub-GeV/c^{2} dark matter using the dual-phase liquid argon time projection chamber of the DarkSide-50 experiment with an exposure of (12 306±184) kg d.
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