We proposed a solid-state powder-metallurgy method named deformation-driven metallurgy (DDM) and fabricated aluminum (Al) matrix composites (AMCs) reinforced by high entropy alloy (HEA) particles. The microstructural evolution and the enhanced mechanical properties of the fabricated AMCs have been characterized. And furtherly, the recrystallization behavior, interfacial diffusion behavior and the underlying strengthening mechanisms of the fabricated AMCs have also been revealed. The incorporated HEAs reinforcements broke into small granules and distributed uniformly in AMCs, and the average grain size of the fabricated AMCs decreased to 1.32 μm. The incorporated HEAs reinforcements formed strong interfacial bonding with Al matrix and the average thickness of the diffusion layers was only about 0.30 μm. Disc-shaped second phases of Al7Cr series emerged under the effect of Cr segregation. The yield strength and tensile strength of the fabricated AMCs enhanced by 91.2
In this work, multiphase engineering was used to tailor the electronic and nonlinear optical (NLO) characteristics of NiCoS2 (NCO) nanocomposites through the formation of defect-rich heterointerfaces and localized electronic states. Presented multiphase engineered NCO nanocomposites were synthesized by a solvothermal method and characterized their structural, morphological, optical, and NLO properties. Raman spectroscopy confirmed coexistence of cubic-Co3S4, hexagonal-CoS, cubic-Ni3S4 and hexagonal-NiS phase architecture. While field-emission scanning electron microscopy (FESEM) has revealed a predominantly spherical morphology, and elemental mapping showed a relatively homogeneous distribution of Ni, Co, and S in NCO nanocomposites. The UV–visible absorption spectrum exhibited strong absorption in the visible range and from which, an optical bandgap was estimated to be 1.6 eV, and an Urbach energy was observed to be 0.3 eV. The photoluminescence (PL) characteristics indicated the involvement of defect-related carrier trapping and reduced radiative recombination pathways, which was contributed to the retention of photoexcited carriers. Furthermore, the nonlinear optical (NLO) properties were investigated using open-aperture Z-scan response, which shown pronounced reverse saturable absorption with yielded a two-photon absorption coefficient around 1.60 × 10− 10 m/W due to the combined effects of interfacial charge transfer, defect-mediated excited-state absorption, and sequential excitation involving localized electronic states. In addition, the optical limiting threshold was observed to be 2.42 × 1012 W/m2 for the NCO nanocomposites, demonstrating attenuation of transmitted laser intensity under high-intensity irradiation. These findings is establishing the NCO nanocomposites as desirable candidates for advance laser-protection application.
We present a microscopic theory of the nonlocal magnetic response of Dirac electrons in graphene under strong perpendicular magnetic fields. Using the relativistic Landau level spectrum and a Kubo-formula approach, we derive the nonlocal orbital magnetic susceptibility and characterize its wavevector- and frequency-dependent inter–Landau-level resonances in the quantum Hall regime. This response originates from inter–Landau-level current correlations and leads to mesoscopic redistribution of magnetic fields over the magnetic-length scale.and leads to mesoscopic redistribution of magnetic fields over the magnetic length scale. We obtain explicit analytical expressions for the response kernel, establish the qualitative difference from conventional two-dimensional electron gases, and provide experimentally measurable signatures for spatial magnetic-field profiles and frequency-dependent resonances. Our results reveal a strongly nonlocal magnetic response associated with relativistic Landau quantization and provide a framework for distinguishing bare inter–Landau-level resonances from possible self-consistent electromagnetic modes.
In this work, a unified three-dimensional finite-difference time-domain framework is used to determine how core-dependent plasmon hybridization translates into optical absorption and solar-weighted response for Au nanoshells with air, SiO₂, TiO₂, and GaP cores represented by their respective optical models. Far-field spectra, near-field distributions, material-resolved absorption, and complementary geometries are analyzed under controlled conditions to distinguish the effects of core optical properties, relative nanoshell geometry, and absolute particle size. Material-resolved analysis further shows that intrinsic core absorption contributes only approximately 1.73
Strain engineering has emerged as an effective approach for improving the thermoelectric performance of two-dimensional materials; however, the coupled regulation of electronic and phonon transport in bilayer TMDs remains insufficiently understood. In this work, the strain-dependent thermoelectric properties of bilayer PtSe2 are systematically investigated using first-principles calculations combined with Boltzmann transport theory and anharmonic phonon transport calculations. The results show that biaxial compressive strain simultaneously enhances the power factor and suppresses the lattice thermal conductivity, resulting in a significant improvement in thermoelectric performance. Under 6
