Quantum Stoner-Wohlfarth Model

Quantum Stoner-Wohlfarth Model.

The quantum mechanical counterpart of the famous Stoner-Wohlfarth model-an easy-axis magnet in a tilted magnetic field-is studied theoretically and through simulations as a function of the spin size S in a sweeping longitudinal field. Beyond the classical Stoner-Wohlfarth transition, the sweeping field-induced adiabatic change of states slows down as S increases, leading to a dynamical quantum ...

Switching behavior of a Stoner–Wohlfarth particle subjected to spin-torque effect

Efficient modeling of vector hysteresis using a novel Hopfield neural network implementation of Stoner–Wohlfarth-like operators

Incorporation of hysteresis models in electromagnetic analysis approaches is indispensable to accurate field computation in complex magnetic media. Throughout those computations, vector nature and computational efficiency of such models become especially crucial when sophisticated geometries requiring massive sub-region discretization are involved. Recently, an efficient vector Preisach-type hy...

Magnetic Dynamics of Nanoscale Magnets: From Classical to Quantum

The various uncommon properties of magnetic nanoparticles (Stoner nanoparticles) and molecular magnets have attracted much attention in industry as well as in the academic community. In this review we begin with going through important experiments in this field and possible applications of these materials. Then we introduce the theoretic models currently used for Stoner nanoparticles and molecu...

Magnetic characterization and interaction modeling of zerovalent iron nanoparticles for the remediation of contaminated aquifers.

Nanoscale zerovalent iron (NZVI), promising for in situ degradation of many environmental contaminants, has been shown to aggregate reducing reactivity and mobility. Aggregation is attributed to the magnetic attractive forces between particles. In this study an alternating gradient force magnetometer (AGFM) is used to measure magnetic properties of NZVI. The magnetization curve is modeled accor...