Low power nonlinear effects in the ferromagnetic resonance of Zn2Y and MnZnY hexagonal ferrites

Silber, L.; Patton, Carl E.; Naqvi, H. F.

doi:10.1063/1.332537

Cited by 20 publications

(5 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The onset of the foldover and bistability effects also occur in magnetic systems when the resonance shift reaches a critical value which was initially investigated by Anderson and Suhl [322]. However in the experimental search for foldover effects in magnetic systems, large discrepancies from the Anderson-Suhl model have been found [324][325][326][327][328][329][330][331][332][333][334][335][336]. These discrepancies were partially due to the presence of spin wave instabilities and thermal effects, which made the interpretation of early experiments difficult, but the primary reason that the critical frequency shift could not be reached is due to the effect of nonlinear damping, which effectively pushes the power and frequency required to observe foldover effects beyond the range initially investigated.…”

Section: Electrical Detection Of Nonlinear Magnetization Dynamicsmentioning

confidence: 99%

Electrical detection of magnetization dynamics via spin rectification effects

2016

View full text Add to dashboard Cite

The purpose of this article is to review the current status of a frontier in dynamic spintronics and contemporary magnetism, in which much progress has been made in the past decade, based on the creation of a variety of micro-and nano-structured devices that enable electrical detection of magnetization dynamics. The primary focus is on the physics of spin rectification effects, which are well suited for studying magnetization dynamics and spin transport in a variety of magnetic materials and spintronic devices. Intended to be intelligible to a broad audience, the paper begins with a pedagogical introduction, comparing the methods of electrical detection of charge and spin dynamics in semiconductors and magnetic materials respectively. After that it provides a comprehensive account of the theoretical study of both the angular dependence and line shape of electrically detected ferromagnetic resonance (FMR), which is summarized in a handbook formate easy to be used for analyzing experimental data. We then review and examine the similarity and differences of various spin rectification effects found in ferromagnetic films, magnetic bilayers and magnetic tunnel junctions, including a discussion of how to properly distinguish spin rectification from the spin pumping/inverse spin Hall effect generated voltage. After this we review the broad applications of rectification effects for studying spin waves, nonlinear dynamics, domain wall dynamics, spin current, and microwave imaging. We also discuss spin rectification in ferromagnetic semiconductors. The paper concludes with both historical and future perspectives, by summarizing and comparing three generations of FMR spectroscopy which have been developed for studying magnetization dynamics.

show abstract

Section: Electrical Detection Of Nonlinear Magnetization Dynamicsmentioning

confidence: 99%

Electrical detection of magnetization dynamics via spin rectification effects

2016

View full text Add to dashboard Cite

show abstract

“…The three experimental parameters are the frequency , the input power , and the absorbed power . Useful reduced frequency, input power, and absorbed power parameters may be defined by (8) (9) and (10) respectively. The numerators for these new parameters have units of frequency, and the common divisors produce dimensionless parameters with the frequency numerators scaled to the low power FMR linewidths.…”

Section: B Reduced Parameter Analysismentioning

confidence: 99%

Nonlinear ferromagnetic resonance and foldover in yttrium iron garnet thin films-inadequacy of the classical model

1999

View full text Add to dashboard Cite

A thin-film resonator structure has been used for quantitative measurements of ferromagnetic resonance foldover and the associated bistable power response for yttrium iron garnet (YIG) thin films. The resonator consisted of a 1-mm by 1-mm-square, 4.9-m-thick epitaxial YIG film on top of a 50m-wide, 3-mm-long microstrip transducer. A static magnetic field of 3200 Oe was applied perpendicular to the film. Loworder magnetostatic forward volume wave standing modes were excited at low power levels in the 020-dBm range and detected as resonance dips in reflected power versus frequency spectra over the range 4-5 GHz. At powers in the 0-to +15-dBm range, these dips showed foldover and bistable response characteristics for increasing and decreasing frequency or power sweeps. The use of 1-10-s-wide pulses instead of continuous-wave (CW) excitation resulted in the consistent disappearance of the foldover and bistability characteristics. The frequency sweep pulse data at fixed power reproduced the down-sweep CW results, and the pulse data for both increasing and decreasing power at fixed frequency reproduced the increasing-power CW results. A quantitative theoretical analysis demonstrates that observed foldover and bistable response characteristics are much weaker than predicted from the classical precession foldover mechanism proposed by Anderson and Suhl, in which the decrease in the static component of the magnetization drives the response. The up-sweep and down-sweep foldover frequency jumps both occur sooner than predicted by this classical mechanism and the calculated foldover profiles are much more severe than the data show.

show abstract

“…A wide variety of nonlinear effects can be observed even at modest power levels, still in the mW range. Three basic effects have been studied to date: ͑1͒ FMR foldover effects, [3][4][5][6][7][8] ͑2͒ auto oscillations which may evolve into a chaotic microwave response under certain conditions, 9 ͑3͒ modifications in the below resonance response at high power levels under conditions which correspond to parallel pumping or subsidiary absorption responses connected with first-order instability processes. 10 Critical to the fundamental understanding of the nonlinear effects listed above is a working knowledge of the critical spin-wave modes which are excited above thermal levels at the onset of the nonlinear behavior.…”

Section: Introductionmentioning

confidence: 99%

Butterfly curves and critical modes for second-order spin-wave instability processes in yttrium iron garnet films

Kaboš

Patton

Wiese

et al. 1996

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

Highresolution xraydiffraction analysis of epitaxially grown yttrium iron garnet films on gadolinium gallium garnet Subsidiary absorption spin wave instability processes in yttrium iron garnet thin films, critical modes, and the ''kink'' effect Combined Brillouin light-scattering ͑BLS͒ and microwave pumping techniques were used to measure the second-order spin-wave instability threshold microwave field amplitudes and characterize the critical modes for ferromagnetic resonance ͑FMR͒ saturation in 4.15 m-thick yttrium iron garnet films at 8.47 GHz with the static magnetic field in-plane. To the best of our knowledge, this work represents the first BLS measurements for second-order FMR saturation processes in ferrite materials. Several new results were obtained: ͑1͒ A new type of butterfly curve for second-order processes. ͑2͒ Strong scattering from modes at low wave numbers in the 10 4 rad/cm range. ͑3͒ An observed in-plane propagation direction for these low wave number modes at 90°to the in-plane static field direction. These results differ significantly from the behavior expected from the bulk sample instability theories of Suhl and Schlömann, which predict critical modes at wave numbers and propagation directions in the 10 5 -10 6 rad/cm and 0°ranges, respectively, and a sharp cusplike response centered at FMR. These results indicate that significant modifications of the bulk theory, which take into account the real modes supported by the film, are needed to realistically model second-order instability processes in films.

show abstract

Low power nonlinear effects in the ferromagnetic resonance of Zn2Y and MnZnY hexagonal ferrites

Cited by 20 publications

References 16 publications

Electrical detection of magnetization dynamics via spin rectification effects

Electrical detection of magnetization dynamics via spin rectification effects

Nonlinear ferromagnetic resonance and foldover in yttrium iron garnet thin films-inadequacy of the classical model

Butterfly curves and critical modes for second-order spin-wave instability processes in yttrium iron garnet films

Contact Info

Product

Resources

About