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There are two common methods in generating magnetic resonance in FMs for spin pumping, cavity FMR and microstrip waveguides [3,7,8,12,19]. FMR cavities produce modest-strength, uniform rf fields over a relatively large space (cm-scale); while microstrip waveguides produce rf fields typically in micron to sub-mm scale, and when made very close to the FMs, can generate fairly large h rf [12,19]. Since the magnitude of rf field determines the excitation strength for spin pumping and only a few reports on microstrip spin pumping presented values of h rf [12,19], in this letter, we mainly compare our results with previous reports of spin pumping using cavity FMR. respectively, which reach the resolution limit of conventional high-resolution XRD systems, demonstrating excellent crystalline quality. In this letter, we focus on two 20-nm YIG films (YIG-1 and YIG-2) for FMR and spin pumping measurements.Room-temperature FMR measurements of the YIG films are carried out in a cavity at a microwave frequency f = 9.65 GHz and power P rf = 0.2 mW. Figure 3e shows the angular dependence of V ISHE for Pt/YIG-1 and W/YIG-2 normalized by the maximum magnitude of V ISHE at θ H = 90°.The clear sinusoidal shape is characteristic of ISHE since [15]thus confirming that the observed ISHE voltage arises from FMR spin pumping. The spin pumping signals we observed in insulating YIG cannot be explained by artifacts due to thermoelectric or magnetoelectric effects, such as anisotropic magnetoresistance (AMR) or anomalous Hall effect (AHE) [13,16,32,34,35].While a spin current is generated by transfer of angular momentum from YIG to metal, simultaneously, the coupling between YIG and metal exerts an additional damping to the magnetization precession in YIG, resulting in increased linewidths [10,12], as shown in Fig. 5 4 for the three samples before (∆H 0 ) and after (∆H 1 ) the deposition of where G r , γ, and B are the real part of spin mixing conductance, the gyromagnetic ratio, factor and Bohr magnetron, respectively. Using Eq. (2), we obtain = 4.56× 10 14 and 2.30× 10 14 Ω -1 m -2 for Pt/YIG-2 and W/YIG-2, respectively, which agree with the theoretical calculations [36] and are among the highest of reported experimental values [3,5,8,9].Previously, spin pumping of Pt/YIG excited by similar cavity FMR gave ISHE voltages in the µV range [1,9,11,16]. The large spin pumping signals and high spin mixing conductance observed in our YIG films may be attributed to two possible reasons. First, the small thickness (20 nm) of our films compared to LPE films (100 nm or larger) may play an important role, as suggested by a recent report [7] that a 200-nm YIG film shows much higher spin pumping efficiency than 1-µm and 3-µm films excited by a microstrip waveguide. [7,12]. Further investigation of spin pumping in these thin YIG films using microstrip waveguides will access larger dynamic range of spin pumping. In addition, the mV-level ISHE voltages reported here using a moderate h rf will allow miniaturization of spin pumping structures while m...

We report the manipulation of nitrogen vacancy (NV) spins in diamond when nearby ferrimagnetic insulator, yttrium iron garnet, is driven into precession. The change in NV spin polarization, as measured by changes in photoluminescence, is comparable in magnitude to that from conventional optically detected magnetic resonance, but relies on a distinct mechanism as it occurs at a microwave frequency far removed from the magnetic resonance frequency of the NV spin. This observation presents a new approach to transferring ferromagnetic spin information into a paramagnet and then transducing the response into a robust optical signal. It also opens new avenues for studying ferromagnetism and spin transport at the nanoscale.

We demonstrate tuning of magnetocrystalline anisotropy in high-quality Sr(2)FeMoO(6) epitaxial films over a range of several thousand Gauss using strain induced by epitaxial growth on substrates of varying lattice constants. Spectroscopic measurements reveal a striking, linear dependence of the out-of-plane anisotropy on the strain-induced tetragonal distortion of the Sr(2)FeMoO(6) lattice. This anisotropy can be tuned from +2000 to -3300 Oe, a range sufficient to rotate the easy axis from in plane to out of plane. Combined with its half-metallicity and high Curie temperature, this result implies a broad range of scientific and technological applications for this novel spintronic material.

We present the growth of thin films of the organic-based ferrimagnetic semiconductor V[TCNE]x (x ∼ 2, TCNE: tetracyanoethylene) via chemical vapor deposition. Under optimized growth conditions, we observe a significant increase in magnetic homogeneity, as evidenced by a Curie temperature above 600 K and sharp magnetization switching. Further, ferromagnetic resonance studies reveal a single resonance with full width at half maximum linewidth of 1.4 G, comparable to the narrowest lines measured in inorganic magnetic materials and in contrast to previous studies that showed multiple resonance features. These characteristics are promising for the development of high frequency electronic devices that take advantage of the unique properties of this organic-based material, such as the potential for low cost synthesis combined with low temperature and conformal deposition on a wide variety of substrates.