ENERGY DENSITY SPECTRUM AND AUTOCORRELATION FUNCTION OF ANOMALIES DUE TO SIMPLE MAGNETIC MODELS*Formulae of the energy spectrum and autocorrelation function have been derived for magnetic anomalies due to four classes of bodies which can be represented in turn by (a) poles, (b) line of poles, (...
Magnet typeMagnetic energyBHmax(kJ/m3)1986 ($/kg)Density (kg/m3)Cost/joule ($/J) Hard ferrite291244001.8 Alnico453072004.9 SmCo220335820012.5 NdFeB29033574008.5 Analogous to the Sm–Co magnet, the price of Nd–Fe–B is expected to decrease and may fall below $100/kg. The cost per joule...
The analytical formula in Eq. (3), and the parameter values can be found in “Experimental designs”. Full size image Results Free energy amplification by the magnetic field We consider a closed quantum system of a particle with mass m and charge q. The notations p, x are the momentum ...
Calculations were done within the framework of spin-polarized density functional theory (DFT) as implemented in the Vienna ab-initio simulation package (VASP). The Perdew–Burke–Ernzerhof (PBE) version of generalized-gradient approximation (GGA) was adopted to describe the exchange–correlation interac...
where ω is the angular frequency, ρ is the MNP density, T is the working temperature, and τ is the relaxation time (τN or τB).17 It is worth mentioning that the Néel relaxation time depends exponentially on the core volume (V), while the Brown mechanism involves the hydrodynamic ...
Bottom: Simulations with initial energy density distribution tilting (, see App. B1) Full size image 3.2 Impact of the magnetic field of chiral origin In this section, we examine separately the contributions of magnetic fields of classic and chiral origin, as given in Eqs. (1–3). To this...
If we can obtain accurate force-free coronal magnetic field models we can calculate the free magnetic energy in the corona, a quantity which is important for the prediction of flares and coronal mass ejections. Knowledge of the 3D structure of magnetic field lines also help us to interpret ...
Spin-Density Oscillations in Ferromagnetic Alloys. I. \"Localized\" Solute Atoms: Al, Si, Mn, V, and Cr in Fe The internal magnetic fields and isomer shifts of Fe57 nuclei in a number of iron-rich bcc binary alloy systems were measured by the Mssbauer technique. The added solute atoms...
The electronic structures were carried out in the framework of density functional theory as implemented in the Vienna ab initio simulation package57,58with the projector augmented wave method59and Perdew, Burke, and Ernzerh of exchange correlation functionals60. The result of calculated electronic stru...
The last term, Mhklε2, is elastic strain energy density, ε is intrinsic residual strain, and Mhkl is the biaxial modulus, which is closely related to the crystallographic direction. It should be noted that we used an amorphous SiO2/Si substrate, and therefore, γi can be neglected. ...