Manipulation of Time- and Frequency-Domain Dynamics by Magnon-Magnon Coupling in Synthetic Antiferromagnets

Magnons (the quanta of spin waves) could be used to encode information in beyond Moore computing applications. In this study, the magnon coupling between acoustic mode and optic mode in synthetic antiferromagnets (SAFs) is investigated by micromagnetic simulations. For a symmetrical SAF system, the time-evolution magnetizations of the two ferromagnetic layers oscillate in-phase at the acoustic mode and out-of-phase at the optic mode, showing an obvious crossing point in their antiferromagnetic resonance spectra. However, the symmetry breaking in an asymmetrical SAF system by the thickness difference, can induce an anti-crossing gap between the two frequency branches of resonance modes and thereby a strong magnon-magnon coupling appears between the resonance modes. The magnon coupling induced a hybridized resonance mode and its phase difference varies with the coupling strength. The maximum coupling occurs at the bias magnetic field at which the two ferromagnetic layers oscillate with a 90° phase difference. Besides, we show how the resonance modes in SAFs change from the in-phase state to the out-of-phase state by slightly tuning the magnon-magnon coupling strength. Our work provides a clear physical picture for the understanding of magnon-magnon coupling in a SAF system and may provide an opportunity to handle the magnon interaction in synthetic antiferromagnetic spintronics.

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Measuring acoustic mode resonance alone as a sensitive technique to extract antiferromagnetic coupling strength

Physical Review B ◽

10.1103/physrevb.92.064418 ◽

2015 ◽

Vol 92 (6) ◽

Cited By ~ 5

Author(s):

Yajun Wei ◽

Peter Svedlindh ◽

Mikhail Kostylev ◽

Mojtaba Ranjbar ◽

Randy K. Dumas ◽

...

Keyword(s):

Coupling Strength ◽

Acoustic Mode ◽

Antiferromagnetic Coupling ◽

Sensitive Technique

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Observation of coupled mechanical resonance modes within suspended 3D nanowire arrays

Nanoscale ◽

10.1039/d0nr06659a ◽

2020 ◽

Vol 12 (43) ◽

pp. 22042-22048

Author(s):

Yasin Kilinc ◽

M. Çagatay Karakan ◽

Yusuf Leblebici ◽

M. Selim Hanay ◽

B. Erdem Alaca

Keyword(s):

Coupling Strength ◽

Nanowire Arrays ◽

Collective Modes ◽

Mechanical Resonance ◽

Resonance Modes ◽

Definition Of

Collective modes are observed in vertically stacked arrays of nanowires suspended between couplers with the coupling strength controlled through the lithographic definition of coupler stiffness.

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Antiferromagnetic resonance modes for theS= 1/2 kagome antiferromagnet Cs2Cu3SnF12

Journal of Physics Conference Series ◽

10.1088/1742-6596/302/1/012011 ◽

2011 ◽

Vol 302 ◽

pp. 012011

Author(s):

S Sharmin ◽

I Umegaki ◽

H Tanaka ◽

T Ono ◽

G Tanaka ◽

...

Keyword(s):

Antiferromagnetic Resonance ◽

Resonance Modes

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Splitting of antiferromagnetic resonance modes in the quasi-two-dimensional collinear antiferromagnet Cu(en)(H2O)2SO4

Physical Review B ◽

10.1103/physrevb.101.014414 ◽

2020 ◽

Vol 101 (1) ◽

Author(s):

V. N. Glazkov ◽

Yu. V. Krasnikova ◽

I. K. Rodygina ◽

J. Chovan ◽

R. Tarasenko ◽

...

Keyword(s):

Two Dimensional ◽

Antiferromagnetic Resonance ◽

Resonance Modes

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Multistability in a star network of Kuramoto-type oscillators with synaptic plasticity

Scientific Reports ◽

10.1038/s41598-021-89198-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Irmantas Ratas ◽

Kestutis Pyragas ◽

Peter A. Tass

Keyword(s):

Synaptic Plasticity ◽

Time Scales ◽

Phase Difference ◽

Coupling Strength ◽

Coupled Oscillators ◽

Analytical Approach ◽

Boundary Function ◽

Phase Oscillators ◽

Star Network ◽

Small Parameters

AbstractWe analyze multistability in a star-type network of phase oscillators with coupling weights governed by phase-difference-dependent plasticity. It is shown that a network with N leaves can evolve into $$2^N$$ 2 N various asymptotic states, characterized by different values of the coupling strength between the hub and the leaves. Starting from the simple case of two coupled oscillators, we develop an analytical approach based on two small parameters $$\varepsilon$$ ε and $$\mu$$ μ , where $$\varepsilon$$ ε is the ratio of the time scales of the phase variables and synaptic weights, and $$\mu$$ μ defines the sharpness of the plasticity boundary function. The limit $$\mu \rightarrow 0$$ μ → 0 corresponds to a hard boundary. The analytical results obtained on the model of two oscillators are generalized for multi-leaf star networks. Multistability with $$2^N$$ 2 N various asymptotic states is numerically demonstrated for one-, two-, three- and nine-leaf star-type networks.

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Effect of nonuniform perpendicular anisotropy in ferromagnetic resonance spectra in magnetic nanorings

Scientific Reports ◽

10.1038/s41598-021-93597-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

E. Saavedra ◽

A. Riveros ◽

J. L. Palma

Keyword(s):

Ferromagnetic Resonance ◽

High Frequency ◽

Lower Energy ◽

Spatial Localization ◽

Dynamic Susceptibility ◽

Perpendicular Anisotropy ◽

Resonant Frequencies ◽

Micromagnetic Simulations ◽

Resonance Modes ◽

Variable Anisotropy

AbstractThe high frequency dynamic behaviors of magnetic nanorings with variable anisotropy along their radius have been studied using micromagnetic simulations. The dynamic susceptibility spectrum and spatial localization of the ferromagnetic resonance modes are investigated by varying anisotropy gradients in nanorings of 200 nm of external radius, with different internal radii. Both the resonant frequencies and the number of peaks depend on the lower energy magnetization configuration which in turn is a function of anisotropy gradients. Besides, it is shown that the effects of the anisotropy gradient are relevant even for the narrowest ring of 10 nm wide. The idea of controlling frequencies by modifying the anisotropy gradients of the system suggests the possibility of using these nanostructures in potential magnetic controllable frequency devices.

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Ultrastrong photon-to-magnon coupling in multilayered heterostructures involving superconducting coherence via ferromagnetic layers

Science Advances ◽

10.1126/sciadv.abe8638 ◽

2021 ◽

Vol 7 (25) ◽

pp. eabe8638

Author(s):

Igor A. Golovchanskiy ◽

Nikolay N. Abramov ◽

Vasily S. Stolyarov ◽

Martin Weides ◽

Valery V. Ryazanov ◽

...

Keyword(s):

Coupling Strength ◽

Information Exchange ◽

Microscopic Mechanism ◽

Phase Velocities ◽

Ferromagnetic Layers ◽

Coupling Parameters ◽

Efficient Information ◽

Magnetization Precession ◽

On Chip ◽

Multilayered Heterostructures

The critical step for future quantum industry demands realization of efficient information exchange between different-platform hybrid systems that can harvest advantages of distinct platforms. The major restraining factor for the progress in certain hybrids is weak coupling strength between the elemental particles. In particular, this restriction impedes a promising field of hybrid magnonics. In this work, we propose an approach for realization of on-chip hybrid magnonic systems with unprecedentedly strong coupling parameters. The approach is based on multilayered microstructures containing superconducting, insulating, and ferromagnetic layers with modified photon phase velocities and magnon eigenfrequencies. The enhanced coupling strength is provided by the radically reduced photon mode volume. Study of the microscopic mechanism of the photon-to-magnon coupling evidences formation of the long-range superconducting coherence via thick strong ferromagnetic layers in superconductor/ferromagnet/superconductor trilayer in the presence of magnetization precession. This discovery offers new opportunities in microwave superconducting spintronics for quantum technologies.

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