This review summarizes recent first-principles investigations of the electronic structure and magnetism dilute magnetic semiconductors (DMSs), which are interesting for applications in spintronics. Details transition-metal-doped III-V II-VI described, especially how couples to properties an impurity. In addition, underlying mechanism ferromagnetism DMSs is investigated from point view order establish a unified picture that explains chemical trend DMSs. Recent efforts fabricate high-${T}_{C}$...

We demonstrate resistive humidity sensing using a single-layer graphene patch placed on top of SiO₂ layer Si wafer.

We demonstrate that the magnetic properties of diluted semiconductors are dominated by short ranged interatomic exchange interactions have a strong directional dependence. By combining first principles calculations with classical Heisenberg model and Monte Carlo simulations, we reproduce observed critical temperatures broad range semiconductors. also show agreement between theory experiment is obtained only when atoms randomly positioned. This suggests ordering heavily influenced...

The skyrmion racetrack is a promising concept for future information technology. There, binary bits are carried by nanoscale spin swirls-skyrmions-driven along magnetic strips. Stability of the skyrmions critical issue realising this Here we demonstrate that lifetime can be calculated from first principles as function temperature, field and track width. Our method combines harmonic transition state theory extended to include Goldstone modes, with an atomistic Hamiltonian parametrized density...

Abstract Identifying the forces that drive a phase transition is always challenging. The hcp-fcc occurs in cobalt at ~700 K has not yet been fully understood, although early theoretical studies have suggested magnetism plays main role stabilization of fcc high temperatures. Here, we perform first principles study free energies these two phases, which break into contributions arising from vibration lattice, electronic and magnetic systems volume expansion. Our analysis energy phases shows...

In this work we examine critically the electronic structure of rare-earth elements by use so-called Hubbard I approximation. From theoretical side all measured features both occupied and unoccupied states are reproduced, without significant deviations between observations theory. We also cohesive properties like equilibrium volume bulk modulus, where find, in general, a good agreement theory measurements. addition, have reproduced spin orbital moments these as they reflected from...

New materials are currently sought for use in spintronics applications. Ferromagnetic with half metallic properties valuable this respect. Here we present the electronic structure and magnetic of binary compounds consisting 3d transition metals group V elements viz. P, Sb As zinc-blende structure. We demonstrate that V, Cr Mn show behavior appropriate lattice constants. By comparing total energies ferromagnetic antiferromagnetic structures, have ascertained phase is stable over one. Of...

We present a first-principles study of the physical properties disordered ${\mathrm{Ni}}_{2\ensuremath{-}x}\mathrm{Mn}\mathrm{Sb}$ alloys which form continuous series connecting two typical members Heusler alloy family: namely, half-metallic semi-Heusler NiMnSb $(x=1)$ and related metallic ${\mathrm{Ni}}_{2}\mathrm{Mn}\mathrm{Sb}$ $(x=0)$. Magnetic moments, exchange interactions, magnon spectra, Curie temperatures at ambient elevated pressures are determined compared with available...

Using both broadband ferromagnetic resonance (FMR) spectroscopy and ab initio calculations, we study the magnetodynamic properties of permalloy $(Py,{\mathrm{Ni}}_{80}{\mathrm{Fe}}_{20})$ ${\mathrm{Py}}_{100\ensuremath{-}x}{\mathrm{M}}_{x}$ films with M as platinum (Pt), gold (Au), or silver (Ag). From uniform FMR mode, extract saturation magnetization $({M}_{S})$, damping $(\ensuremath{\alpha})$, inhomogeneous broadening $(\mathrm{\ensuremath{\Delta}}{H}_{0})$; from first perpendicular...

We present graphene-based CO₂ sensing and analyze its cross-sensitivity with humidity.

We present a computationally efficient general first-principles based method for spin-lattice simulations solids. Our is on combination of atomistic spin dynamics and molecular dynamics, expressed through Hamiltonian where the bilinear magnetic term expanded to second order in displacement, all parameters are computed using density functional theory. The effect first-order coupling magnon phonon dispersion bcc Fe reported as an example, seen be good agreement with previous performed...

We show that magnetic structures involving partial disorder of local moments on the Mn atoms in $({\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x})\mathrm{As}$ lower total energy, compared to case perfect ferromagnetic ordering, when As defects Ga sublattice are present. Such found be stable for a range concentrations antisites, and this result accounts observed critical temperatures $({\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x})\mathrm{As}$. propose an explanation stabilization...

We exploit the decoherence of electrons due to magnetic impurities, studied via weak localization, resolve a long-standing question concerning classic Kondo systems Fe impurities in noble metals gold and silver: which Kondo-type model yields realistic description relevant multiple bands, spin, orbital degrees freedom? Previous studies suggest fully screened spin $S$ model, but value remained ambiguous. perform density functional theory calculations that $S=3/2$. also compare previous new...

We investigate the magnetic properties of a range low-dimensional ferromagnets using combination first-principles calculations and atomistic spin dynamics simulations. This approach allows us to evaluate ground state finite temperature experimentally well characterized systems such as Co/Cu(111), Co/Cu(001), Fe/Cu(001) Fe/W(110), for different thicknesses layer. compare our calculated wave spectra with experimental data available in literature, find good quantitative agreement. also predict...

The half-metallic half-Heusler alloy NiMnSb is a promising candidate for applications in spintronic devices due to its low magnetic damping and rich anisotropies. Here we use ferromagnetic resonance (FMR) measurements calculations from first principles investigate how the composition of epitaxially grown influences magnetodynamic properties saturation magnetization $M_S$, Gilbert $\alpha$, exchange stiffness $A$. $M_S$ $A$ are shown have maximum stoichiometric composition, while minimum. We...

Using micromagnetic simulations, we have investigated spin dynamics in a spin-valve bilayer the presence of thermal gradient. The direction and intensity gradient allow us to excite wave modes each layer selectively. This permits synchronize magnetization precession two layers rectify flows energy through system. Our study yields promising opportunities for applications caloritronics nanophononics devices.

Half-metallicity and low magnetic damping are perpetually sought for in spintronics materials full Heusler alloys this respect provide outstanding properties. However, it is challenging to obtain the well-ordered half-metallic phase as-deposited thin films theory has struggled establish a fundamentals understanding of temperature dependent Gilbert these systems. Here we present study differently ordered Co2FeAl alloy films. The sum inter- intraband electron scattering conjunction with finite...

Atomistic spin dynamics simulations have evolved to become a powerful and versatile tool for simulating dynamic properties of magnetic materials. It has wide range applications, instance switching states in bulk nano-magnets, topological magnets, such as skyrmions vortices domain wall motion. In this review, after brief summary the existing investigation tools study magnons, we focus on calculations spin-wave excitations low-dimensional magnets effect relativistic temperature effects...

We discuss the importance of different exchange mechanisms like double exchange, p–d and anti-ferromagnetic as well ferromagnetic superexchange in dilute magnetic semiconductors (DMSs). Based on coherent potential approximation for electronic structure DMSs we show that exhibit dependences concentration impurities, hybridization with wavefunctions neighbouring impurities position Fermi level band gap. However, common to all is that, long half-metallicity preserved, they are determined by...

We have investigated the electronic structure of fluorite Cu2Se using density functional theory calculations within LDA, PBE and AM05 approximations as well non-local hybrid PBE0 HSE approximations. find that is a zero gap semiconductor when either local or semi-local approximation while opens up gap. For approximation, we presence depends on range separation for exchange. occupied part in states PBE, AM05, agree with regard to overall structure. However, functionals result peaks shifted...