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International audienceIn this work, we investigate silver (Ag) nanoparticle-related plasmonic effect on light absorption in Si substrate. Ag nanoparticles (Ag-NPs) deposited on top of Si were used to capture and couple incident light into these structures by forward scattering. We demonstrate that we can control nanoparticle size and shape while varying deposition time and annealing parameters. By the increase of the total time of the reaction process, morphology of Ag-NPs evolutes affecting the number and the width of surface plasmon resonance peaks, whereas for changed annealing parameters (temperature and time), the effect is more pronounced on the broadening and the position of peaks. Specific morphology of Ag-NPs can exhibit an interesting enhancement of optical properties which enables plasmon-related application in photovoltaic solar cells

In the present research, polycrystalline samples of La0.5Sm0.2Sr0.3Mn1−xCrxO3 are prepared using the self-combustion method.

This study investigates the magnetic properties of Ni0.6Zn0.4Al0.5Fe1.5O4 ceramics as a function of varying temperature. The results show that the sharp change in magnetization at Curie temperatures produces a reasonable magnetic entropy change (ΔS M). The Ni–Zn–Al ferrite is, therefore, predicted to work better than other spinel ferrites with higher efficiencies. Near the second-order transition, the critical exponents are derived from the magnetic entropy change’s field dependency. Their values are close to the mean field model. The reliability of the calculated exponents is confirmed by using scaling theory. The temperature dependence of the dielectric constants shows the presence of phase transitions. In fact, the local disorder provides a frequency that is dependent on relaxor ferroelectric-like behaviors, which is a significant finding in the search for new lead-free relaxor materials. The modified Curie–Weiss law and the Lorentz and Gaussian-type relationships are used to analyze the diffuse phase transition. A correlation between dielectric and magnetic behaviors near the magnetic phase transition temperature (direct observation magnetodielectric effect) is established. Based on these findings, the Ni0.6Zn0.4Al0.5Fe1.5O4 ceramic appears to be a promising candidate for multifunctional device applications.