Magnetostatic Modes in Disks and Rods

Dillon, J. F.

doi:10.1063/1.1735901

Cited by 116 publications

(77 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For a MDM ferrite particle placed inside a microwave cavity with sufficiently low quality factor Q, one can observe the Fano-interference effects in microwave scattering. The spectrum of the MDM oscillations in a ferrite-disk particle is very rich [45,46]. It contains different types of modes: the radial, azimuthal, and thickness modes [30].…”

Section: A Mdm Ferrite Disk and A Microwave Cavity: The Model Of mentioning

confidence: 99%

Magnetic-dipolar-mode Fano resonances for microwave spectroscopy of high absorption matter

Vaisman

Kamenetskii

Shavit

2015

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Study of interaction between high absorption matter and microwave radiated energy is a subject of great importance. Especially, this concerns microwave spectroscopic characterization of biological liquids. Use of effective testing methods to obtain information about physical properties of different liquids on the molecular level is one of the most important problems in biophysics. However, the standard methods based on the microwave resonant techniques are not sufficiently suitable for biological liquids because the resonance peak in a resonator with high-loss liquids is so broad that the material parameters cannot be measured correctly. Although molecular vibrations of biomolecules may have microwave frequencies, it is not thought that such resonant coupling is significant due to their low energy compared with thermal energy and the strongly dampening aqueous environment. This paper presents an innovative microwave sensing technique for different types of lossy materials, including biological liquids. The technique is based on the combination of the microwave perturbation method and the Fano-resonance effects observed recently in microwave structures with embedded magnetic-dipolar quantum dots. When frequency of the magnetic-dipolar-mode (MDM) resonance is not equal to the cavity resonance frequency, one gets Fano transmission intensity. With tuning, by a bias magnetic field, the MDM resonance frequency to the cavity resonance frequency, one observes a Lorentz line shape. Use of an extremely narrow Lorentzian peak allows exact probing the resonant frequency of a cavity loaded by a highlossy-material sample. For different kinds of samples, one has different frequencies of Lorentzian peaks. This gives a picture for precise spectroscopic characterization of high absorption matter in microwaves. PACS number(s) 41.20.Jb, 42.25.Fx, 76.50.+g

show abstract

Section: A Mdm Ferrite Disk and A Microwave Cavity: The Model Of mentioning

confidence: 99%

Magnetic-dipolar-mode Fano resonances for microwave spectroscopy of high absorption matter

Vaisman

Kamenetskii

Shavit

2015

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…A distinctive feature of MDM resonances in small ferrite samples with certain geometrical forms is the fact that because of the bias-field induced anisotropy in a ferrite, one may obtain the real-eigenvalue spectra for scalar wave functions. In microwave experiments with quasi-2D ferrite disks, regular multiresonance MDM spectra have been observed [39][40][41][42][43]. A formulation of quasi-Hermitian eigenvalue problem and analytical spectral solutions for MDMs in these thin-film ferrite disks were shown recently [14][15][16][17].…”

Section: Quasistatic Oscillations In Small Samplesmentioning

confidence: 94%

“…[39,40] obtained at a varying bias magnetic field and a constant operating frequency. The main feature of the multi-resonance line spectra in Refs.…”

Section: Energy Eigenstates Of Mdm Oscillations In a Quasi-2d Ferritementioning

confidence: 99%

See 1 more Smart Citation

Magnetic-Dipolar-Mode Oscillations for Near- And Far-Field Manipulation of Microwave Radiation

Kamenetskii

Joffe²,

Berezin³

et al. 2013

PIER B

View full text Add to dashboard Cite

Abstract-There has been a surge of interest in the subwavelength confinement effects of the electromagnetic fields. Based on these effects, one can obtain new behaviors of the near-and far-field radiation.It is well known that in optics, the subwavelength confinement can be obtained due to surface-plasmon (or electrostatic) oscillations in metal structures. This paper is a review of recent studies on the subwavelength confinement in microwaves due to magnetic-dipolar-mode (MDM) [or magnetostatic (MS)] oscillations in small ferrite samples. MDM oscillations in a mesoscopic ferritedisk particle are quantized oscillations, which are characterized by energy eigenstates. The field structures are distinguished by powerflow vortices and non-zero helicity. Also in vacuum, the near fields originated from MDM particles are designated by topologically distinctive power-flow vortices, non-zero helicity, and a torsion degree of freedom.To differentiate such field structures from regular electromagnetic (EM) field structures, we term them as magnetoelectric (ME) fields. In a pattern of the microwave field scattered by a MDM ferrite disk and MDM-disk arrays, one can observe rotating topological-phase dislocations. This opens a perspective for creation of engineered electromagnetic fields with unique symmetry properties. In the near-field applications, we propose novel microwave sensors for material characterization, biology, and nanotechnology. Strong energy concentration and unique topological structures of the near fields originated from the MDM resonators allow effective measuring chiral properties of materials in microwaves. Generating

show abstract

“…One can suppose a classical mechanism of interaction between the disk eigen electric moment and the cavity Efield. But the question is why this interaction gives the multiresonance spectral pictures similar to the pictures shown in well known experiments with a ferrite disk placed in an external RF magnetic field [7]. The main aspects concern the question how one may obtain effective resonance interactions between the edge double valued functions (determining the anapolemoment properties) and the membrane single valued functions (determining the energy eigen states).…”

mentioning

confidence: 87%

Eigen electric moments and magnetic–dipolar vortices in quasi-2D ferrite disks

2008

View full text Add to dashboard Cite

A property associated with a vortex structure becomes evident from an analysis of confinement phenomena of magnetic oscillations in a quasi-2D ferrite disk with a dominating role of magnetic-dipolar (non-exchange-interaction) spectra. The vortices are guaranteed by the chiral edge states of magnetic-dipolar modes which result in appearance of eigen electric moments oriented normally to the disk plane. Due to the eigen-electric-moment properties, a ferrite disk placed in a microwave cavity is strongly affected by the cavity RF electric field with a clear evidence for multi-resonance oscillations. For different cavity parameters, one may observe the "resonance absorption" and "resonance repulsion" behaviors.PACS numbers: 76.50.+g, 73.22.Gk, In a dot of a ferromagnetic material of micrometer or submicrometer size, a curling spin configuration -that is, a magnetization vortex -has been proposed. The vortex consists of an in-plane, flux-closure magnetization distribution and a central core whose magnetization is perpendicular to the dot plane. It has been shown that under certain conditions a vortex structure will be stable because of competition between the exchange and dipole interactions [1]. In spite of the fact that vortices can appear in different kinds of physical phenomena, yet such "swirling" entities seem to elude an all-inclusive definition. It appears that the character of magnetic vortices in magnetically soft "small" (with the dipolar and exchange energy competition) and magnetically saturated "big" (when the exchange is neglected) ferrite disks is very different. A magnetization vortex in a magnetically soft sample cannot be characterized by some invariant, such as the flux of vorticity. So a vorticity thread may not be defined for the magnetization vortex [2]. At the same time, in magnetically saturated samples with magnetic-dipolar vortices one can observe the flux of the pseudo-electric (gauge) fields [3,4]. The vortices of magneticdipolar-mode (MDM) oscillations in a ferrite disk become apparent due to the symmetry breaking effects which result in appearance of eigen electric moments oriented normally to the disk plane [3 -5].A property associated with a vortex structure in a ferrite disk with a dominating role of magnetic-dipolar (non-exchange-interaction) spectra becomes evident from an analysis of confinement phenomena of magnetic-dipolar oscillations. It has been shown [3,4,6] that for MDMs in a ferrite disk one has evident quantum-like attributes. The spectrum is characterized by energy eigenstate oscillations. It appears, however, that because of the boundary condition on a lateral surface of a ferrite disk, MS-potential eigen functions cannot be considered as single-

show abstract

Magnetostatic Modes in Disks and Rods

Cited by 116 publications

References 12 publications

Magnetic-dipolar-mode Fano resonances for microwave spectroscopy of high absorption matter

Magnetic-dipolar-mode Fano resonances for microwave spectroscopy of high absorption matter

Magnetic-Dipolar-Mode Oscillations for Near- And Far-Field Manipulation of Microwave Radiation

Eigen electric moments and magnetic–dipolar vortices in quasi-2D ferrite disks

Contact Info

Product

Resources

About