Magnetic artificial atoms based on thin-film ferrite disk particles

TL;DR

This paper explores the concept of magnetic artificial atoms using thin-film ferrite disk particles, drawing parallels with semiconductor quantum wells, and investigates high-frequency magnetization dynamics and confinement effects in these magnetic structures.

Contribution

It introduces a phenomenological model of ferrite particles employing the effective-mass approximation and Schrodinger-like equations to analyze energy eigenstates, filling a gap in high-frequency magnetic structure modeling.

Findings

Identification of unique confinement phenomena in ferrite disk particles.

Demonstration of geometrical effects on magnetostatic oscillations.

Revelation of properties akin to artificial atomic structures in magnetic systems.

Abstract

Semiconductor quantum wells can be considered as an example of artificial atoms. Following the ideas used in the effective-mass theory, one can describe electron states in the quantum-well structure based on the Schrodinger-like equation for the envelope function. In recent years, there has been a renewed interest in high frequency dynamic properties of finite size magnetic structures. In a series of new publications, confinement phenomena of high-frequency magnetization dynamics in magnetic particles have been the subject of much experimental and theoretical attention. Till now, however, there are no phenomenological models of a ferrite particle with high-frequency magnetization dynamics that use the effective-mass approximation and the Schrodinger-like equation to analyze energy eigenstates of a whole ferrite-particle system, similarly to semiconductor quantum wells. Magnetostatic (MS) oscillations in ferrite samples have the wavelength much smaller than the electromagnetic wavelength at the same frequency and, at the same time, much larger than the exchange-interaction spin wavelength. This intermediate position between the pure electromagnetic and spin-wave (exchange-interaction) processes reveals very special behaviors of the geometrical effects. The confined effects for MS oscillations in normally magnetized thin-film ferrite disks demonstrate very unique properties of artificial atomic structures.