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• The Gilbert damping in YIG capped by PtSn alloy films increased significantly. • The effective spin mixing conductance and spin Hall angle of PtSn alloy are larger than that of Pt. High efficient nonmagnetic materials for generating and detecting spin currents are extremely sought after for prospective spintronic devices. We investigate the spin pumping and inverse spin Hall effects (ISHE) in Y 3 Fe 5 O 12 (YIG)/ Pt 1-x Sn x (x = 0.06, 0.11, 0.17, 0.23, 0.28) bilayer using a coplanar waveguide based broadband ferromagnetic resonance setup. We find that the measured effective spin mixing conductance g eff ↑ ↓ and spin Hall angle θ SH strongly correlate with the Sn content. A large spin Hall angle θ SH = 0.089 ± 0.001 is obtained in a Pt 0.77 Sn 0.23 alloy film while θ SH = 0.055 ± 0.001 in pure Pt thin film under the same conditions. This enhancement of spin Hall angle is due to skew scattering from the Sn impurities resulting from spin-orbit interaction. Meanwhile, the spin Hall (SH) resistivity of the spin current induced by Sn impurities in Pt has been revealed. The SH resistivity of Pt 1-x Sn x remain pretty low values (0.17–1.1 × 10−9 Ω⋅m), which are promising for construct high-speed spintronic devices exploiting the spin Hall effect. [ABSTRACT FROM AUTHOR]

Abstract In this study, Fe 83 Ga 17 thin films are deposited on Si(1 0 0) and Si(1 1 1) substrates with a Ti layer by using DC magnetron sputtering. The addition of Ti layer does not significantly change the magnetic and magnetostrictive properties of the Fe-Ga film, however it can effectively prevent the abscission of film during heat treatment. The Fe 83 Ga 17 films deposited on Si(1 0 0) and Ti/Si(1 0 0) have relatively small coercive forces, low saturation magnetic fields, and the magnetostriction curves are easily saturated in a low field. The magnetostriction of Fe 83 Ga 17 on Ti/Si(1 0 0) can reach 105 ppm. The Fe 83 Ga 17 thin films on Si(1 1 1) and Ti/Si(1 1 1) have large saturation magnetic fields (about 61Oe) and the magnetostriction curve shows linearity, which can be used in magnetic field detection, micro actuators and magnetoelectric (ME) devices. Dendritic domains and stripe domains are observed in these samples due to the influence of different internal stresses. After a vacuum heat treatment, the internal stress was released. At the same time, the structure of both the dendritic domains and stripe domains turns into a dot domain. The EBSD results show that annealed Fe-Ga films sputtered on a Ti layer have a very weak texture. [ABSTRACT FROM AUTHOR]

In this work, 〈1 0 0〉 textured Co 70 Fe 30 alloy was successfully prepared by directional solidification technique. The effect of heat treatment on magnetostriction and microstructure of Co 70 Fe 30 alloy has been investigated. The Co 70 Fe 30 alloy was annealed in argon atmosphere at 700 °C–900 °C for 9 days and then cooled to room temperature by slow cooling or quenching. The magnetostriction as large as 180 ppm has been achieved for the quenched samples when the annealing temperature is ranging from 820 °C to 860 °C. Structural analyses indicate that the large magnetostriction originates from precipitation of a nanoscale face-centered tetragonal (fct) phase embedded in a body-centered cubic (bcc) phase matrix. [ABSTRACT FROM AUTHOR]

• Rare-earth Dy nano-films with different thicknesses were grown on YIG thin film. • Gilbert damping α increased over 300% for the YIG/Dy(60 nm) compared to the bare YIG. • The enhanced α strongly depends on the out-of-plane magnetic anisotropy field. • Large modulation of magneto-optic Kerr rotation was realized in YIG capped with Dy nano-films. The dynamic magnetization of magnetic materials is of fundamental interest and is essential for various applications in magnetic storage, spin wave and wireless communication areas. Traditionally, rare-earth-doped ferromagnets show an enhancement of the Gilbert damping parameter due to the slow relaxation of the 4f-electron spins of rare-earth atoms. The exchange coupling between a ferromagnetic garnet thin film and a nanometer rare-earth thin film has been rarely explored. In this work, we fabricated and systematically studied microstructural, static and dynamic magnetic properties of yttrium iron garnet (YIG)/dysprosium (Dy) heterojunctions. Large modulations of the out-of-plane magnetic anisotropy field, Gilbert damping parameter and magneto-optic Kerr rotation angle have been realized in single-crystalline YIG thin films capped by rare-earth Dy nano-films. Both the effective Gilbert damping parameter, α eff , and the Kerr rotation angle, increase by 300% for the YIG/Dy(60 nm) heterostruture compared to the bare YIG ferromagnet. The enhanced α eff strongly depends on the out-of-plane magnetic anisotropy field, which arises from the interfacial exchange coupling between YIG and Dy nano-films. Our findings provide a robust route to control both magnetization dynamics and magneto-optic properties using rare-earth nano-films. [ABSTRACT FROM AUTHOR]

• (TmBi) 3 (FeGa) 5 O 12 nanostructured films were sputtered on high quality liquid phase epitaxy Y 3 Fe 5 O 12 films. • Crystal structure and magnetic hysteresis loop measurement indicate interfacial tension between the YIG TBIG films. • The stress induced anisotropy up to 220.0 Oe results in multi-mode ferromagnetic resonance. • The heterostructure induction and strengthening of magnetoelastic coupling between spin and elastic subsystems. We studied the static and dynamic magnetic properties of a Y 3 Fe 5 O 12 /Tm 2.28 Bi 0.72 Fe 4.3 Ga 0.7 O 12 (TBIG) heterostructure. TBIG nanostructured films were sputtered on 300 nm liquid phase epitaxy Y 3 Fe 5 O 12 films at 400 °C and post-annealing in air at 800 °C. X-ray diffraction (XRD) patterns provide evidence of strain-induced lattice mismatch between the Y 3 Fe 5 O 12 and the TBIG films. Strain-induced anisotropy produces multipeak ferromagnetic resonance spectra from the Y 3 Fe 5 O 12 film, and these resonance modes behave differently. Fitting of f - H r data to the Kittel equation yields the anisotropy fields of each resonance mode, indicating the existence of an out-of-plane anisotropic field which is up to 220.9 Oe. We also observe comb-like spin wave spectra causing by the interaction of elastic waves and spin waves in the in-plane and out-of-plane magnetization with peak separation Δ f ≈ 3.24 MHz. [ABSTRACT FROM AUTHOR]

• Large perpendicular magnetic anisotropy was induced in nanometer Bi-YIG films. • First-principles calculations showed Bi can enhance the Young's modulus of YIG. • The linewidth ΔH of Bi-YIG film with PMA is 20 Oe for fields out-of-plane. Ferrimagnetic insulator Bismuth-substituted YIG (Bi 1 Y 2 IG) thin films with thickness from 8.2 nm to 31.7 nm and roughness smaller than 0.5 nm have been grown on substituted Gd 3 Ga 5 O 12 (sGGG) substrate by pulsed laser deposition (PLD). A comprehensive description of the structural characteristics and magnetic properties of Bi-YIG films were given. Thickness-dependent large perpendicular magnetic anisotropy (PMA) was induced in Bi-YIG films by tensile strain originate from lattice mismatch. MOKE and VSM results showed that the 8.2 nm and 17.8 nm film has large PMA, high squareness and small out-of-plane coercivity with a saturation magnetization of 115 emu/cm3. However, with the increasing of film thickness, the easy axis turned from out-of-plane to in-plane. The thickness-dependent PMA indicated that the increase in PMA was caused by the interfacial strain. Furthermore, the Dzyaloshinskii–Moriya interaction (DMI), which is proportional to the strength of spin orbit coupling could also contribute to the increasing of PMA. First-principles calculations were adopted to study the elastic properties of Bi-YIG films. It showed that the Young's modulus of Bi-YIG increased to 225 GPa, which giving a larger K u λ than un-doped YIG films under same strain. The measured peak to peak linewidth ΔH of Bi-YIG film with PMA is 20 Oe for fields out-of-plane. The derived Gilbert damping constant is 7.03 × 10−4, indicating a low magnetic loss. [ABSTRACT FROM AUTHOR]

• Several types of antennas were studied for the excitation and detection of spin waves. • The effect of edge defects of exciting signal line on spin wave excitation has been studied. • Meander-shaped short-circuit line antennas with high wave vector has been designed and studied. • Measurements has been carried out on YIG film with short-circuit line antennas. This paper presents a comprehensive study of antennas based on co-planar waveguides (CPW) for ferromagnetic resonance (FMR) detection and spin wave spectroscopy in ferromagnetic insulators. We studied the FMR detection waveguide for both flip-chip method and on-chip waveguide. An antenna can work with low-wave vectors on commercial substrates such as RO4003/Al 2 O 3 and ferromagnetic insulators such as yttrium iron garnet. A higher value of wave vector k is required by antennas to excite spin wave with a shorter wavelength, which strongly depends on the width of the antenna. A co-plane waveguide antenna can excite k 1 between 0 and 6 rad/μm with the spin wave group velocity and excitation-spectrum width Δ k = 3.58 rad/μm and inner signal line 0.5 μm. The value of k 1 for antenna excited spin wave using a 0.5 μm short-circuit line of CPW varied between 0 and 7 rad/μm with Δk = 1.98 rad/μm. Antennas with different width (0.5–10 μm) were also studied. Meander-shaped short-circuit lines were designed to modify the k vector. The maximum amplitude of the k vector of the designed antenna appeared at k 3 ≈ 3 rad/μm for the line width of 0.5 μm. [ABSTRACT FROM AUTHOR]