Spin pumping has been considered a powerful tool to manipulate the spin current in a ferromagnetic/nonmagnetic (FM/NM) system, where the NM part exhibits large spin-orbit coupling (SOC). In this work, the spin pumping in β-W/Interlayer (IL)/CoFeAl (CFA) heterostructures grown on Si(100 is systematically investigated with different ILs in which SOC strength ranges from weak to strong. We first measure the spin pumping through the enhancement of effective damping in CFA by varying the thickness of β-W.
View Article and Find Full Text PDFThis paper presents an investigation on micropipe evolution from hexagonal voids in physical vapor transport-grown 4H-SiC single crystals using the cathodoluminescence (CL) imaging technique. Complementary techniques optical microscopy, scanning electron microscopy, and energy-dispersive spectroscopy (EDS) are also used to understand the formation mechanism of hexagonal voids along with the origin of pipes from these voids. The ability of CL to image variations along the depth of the sample provides new insights on how micropipes are attached to hexagonal voids that lie deep within the bulk single crystals.
View Article and Find Full Text PDFMagnetic skyrmions are topological spin-textures having immense potential for energy efficient spintronic devices. Here, we report the observation of stable skyrmions in unpatterned Ta/CoFeAl(CFA)/MgO thin film heterostructures at room temperature in remnant state employing magnetic force microscopy. It is shown that these skyrmions consisting of ultrathin ferromagnetic CFA Heusler alloy result from strong interfacial Dzyaloshinskii-Moriya interaction (i-DMI) as evidenced by Brillouin light scattering measurements, in agreement with the results of micromagnetic simulations.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
January 2018
In this paper, we have reported a simple and efficient method for the synthesis of uniform, highly conducting single or few layer molybdenum disulfide (MoS2) on large scale. Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) have been used for the confirmation of mono or few layered nature of the as-synthesized MoS2 sheets. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD) and Raman Spectroscopy have also been used to study the elemental, phase, and molecular composition of the sample.
View Article and Find Full Text PDFCorrection for 'One step in situ synthesis of CeO2 nanoparticles grown on reduced graphene oxide as an excellent fluorescent and photocatalyst material under sunlight irradiation' by Animesh Kumar Ojha et al., Phys. Chem.
View Article and Find Full Text PDFCeO2 nanoparticles (NPs) with average particle size of ∼17 nm were grown on graphene sheets by simply mixing cerium chloride as the Ce precursor with graphene oxide (GO) in distilled water and the simultaneous reduction of GO to reduced graphene oxide (rGO), followed by a one-step hydrothermal treatment at 150 °C. A unique blue to green tuneable luminescence was observed as a function of the excitation wavelength. With this method, significant applications of rGO-CeO2 nanocomposites in many optical devices could be realized.
View Article and Find Full Text PDFThe present study aims to deduce the confinement effect on the magnetic properties of iron carbide (Fe3C) nanorods filled inside carbon nanotubes (CNTs), and to document any structural phase transitions that can be induced by compressive/tensile stress generated within the nanorod. Enhancement in the magnetic properties of the nanorods is attributed to tensile stress as well as to compression, present in the radial direction and along the nanotube axis, respectively. Finally, the growth of permanent cylindrical nanomagnets has been optimized by applying a field gradient.
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