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Spin waves (SWs) are promising objects for signal processing and future quantum technologies due to their high microwave frequencies with corresponding nanoscale wavelengths. However, the nano‐wavelength SWs generated so far are limited to low frequencies. In the paper, using micromagnetic simulations, it is shown that a microwave‐pumped SW mode confined to the cavity of a thin film magnonic crystal (MC) can be used to generate waves at tens of GHz and wavelengths well below 50 nm. These multi‐frequency harmonics of the fundamental cavity mode are generated when the amplitude of the pumping microwave field exceeds a threshold, and their intensities then scale linearly with the field intensity. The frequency of the cavity mode is equal to the ferromagnetic resonance frequency of the planar ferromagnetic film, which overlaps with the magnonic bandgap, providing an efficient mechanism for confinement and magnetic field tunability. The effect reaches saturation when the microstrip feed line covers the entire cavity, making the system feasible for realization. [ABSTRACT FROM AUTHOR]

Magnetic hopfions are localized magnetic solitons with a nonzero 3D topological charge (Hopf index). Herein, an analytical calculation of the magnetic hopfion gyrovector is presented and it is shown that it does not vanish even in an infinite sample. The calculation method is based on the concept of the emergent magnetic field. The particular case of the simplest nontrivial toroidal hopfion with the Hopf index |QH|=1$\left|\right. Q_{\text{H}} \left|\right. = 1$ in the cylindrical magnetic dot is considered and dependencies of the gyrovector components on the dot sizes are calculated. Nonzero hopfion gyrovector is important in any description of the hopfion dynamics within the collective coordinate Thiele's approach. [ABSTRACT FROM AUTHOR]

Inclusion of spin waves into the computing paradigm, where complementary metal‐oxide‐semiconductor devices are still at the fore, is now a challenge for scientists around the world. In this work, a wave phenomenon that has not yet been used in magnonics‐self‐imaging, also known as the Talbot effect, to design and simulate the operation of interference systems that perform logic functions on spin waves in thin ferromagnetic multimode waveguides is utilized. Lookup tables operating in this way are characterized by high programmability and scalability; thanks to which they are promising for their implementation in field‐programmable gate arrays circuits, where multiple logic realizations can be obtained. [ABSTRACT FROM AUTHOR]

Background and Purpose: Many stroke trials include maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP) outcome measurements. However, data on agreement and reliability of repeated MIP, MEP, and SNIP measurements in acute and subacute stroke patients are scarce. Methods: This study employed a test–retest design. Eighteen patients (seven female) with mean (SD) age 59 (14.5) years were recruited from neurological wards. Median (range) time since first stroke was 50.5 (21–128) days. MIP, MEP, and SNIP were measured repeatedly in three testing sessions (S1–3) conducted within 24 h and following international standards. Intra‐rater agreement between testing sessions was analyzed using the Bland–Altman method. Test–retest reliability was analyzed using intra‐class correlation coefficient (ICC). Association between individual measurement variability, time poststroke, and level of stroke impairment was analyzed using Spearman's rho. Results: Mean difference and 95% limits of agreement for MIP were −0.40 (−23.02, 22.22) cmH2O between S1 and S2, and 2.14 (−12.79, 16.99) cmH2O between S2 and S3; for MEP, −4.56 (−29.01, 19.90) cmH2O between S1 and S2, and 0.29 (−24.28, 24.87) cmH2O between S2 and S3; and for SNIP, −10.56 (−38.48, 17.37) cmH2O between S1 and S2, and −6.06 (−27.32, 15.20) cmH2O between S2 and S3. ICCs for MIP, MEP, and SNIP were ≥0.9 throughout. There were no strong correlations between individual measurement variability and time poststroke or level of stroke impairment. Discussion: MIP, MEP, and SNIP in acute and subacute stroke patients show good test–retest reliability for group averages; however, absolute agreement can vary considerably for some individuals. [ABSTRACT FROM AUTHOR]

Not only in fundamental wave physics but also in technical areas such as radar and communication systems, high‐frequency magnonics is increasingly attracting attention. Here, time‐resolved scanning transmission X‐ray microscopy is used to directly image high‐frequency spin wave propagation in cobalt‐iron waveguides at excitation frequencies above 10 GHz. In addition, an excitation technique is presented, which allows for versatile pump–probe experiments with radio frequency currents up to 30 GHz. With this approach, a global sinusoidal magnetic field excitation is applied to induce spin waves from the waveguide edges. Amplitude, relative phase, and k‐space information as a function of excitation frequencies and static external fields are observed, matching the theoretical predictions for confined waveguide structures. In doing so, the foundation for high‐frequency multimode spin wave excitation and propagation at the nanoscale is laid, which can be a prospective path in radar and communication systems. [ABSTRACT FROM AUTHOR]

Spin waves in 2D periodic magnetic nanocomposites are studied by means of the plane wave method. The effect of the ellipticity and in-plane rotation of the scattering centers on the band structure is investigated, to indicate new possibilities of fine tuning of spin-wave filter passbands. [ABSTRACT FROM AUTHOR]

The calculations of the inelastic spin wave scattering by flexure vibrations of the Bloch domain wall (Winter's magnons) in thin magnetic films are presented. The approach is based on the interaction of the propagating spin waves with the dynamical emergent electromagnetic field generated by the moving inhomogeneous magnetization texture (domain wall). The probability of the spin wave scattering for the Winter's magnon emission and absorption processes essentially rises with the spin wave scattering angle increase up to 90°. The angular dependence of the scattering probability is essentially stronger for the magnon absorption processes that allow distinguishing these elementary emission/absorption processes experimentally. [ABSTRACT FROM AUTHOR]