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Canted antiferromagnets offer great potential in fundamental research and for use in applications due to their unique properties. The presence of the Dzyaloshinskii–Moriya interaction (DMI) leads to the existence of a weak ferromagnetic moment at room temperature. We study both theoretically and experimentally microwave spin pumping by a quasi-ferromagnetic mode from a canted easy plane antiferromagnet with weak ferromagnetism FeBO3. The conversion of a microwave signal into a constant voltage is realized using the inverse spin Hall effect in an iron borate/heavy metal heterostructure. We use an additional bias magnetic field to selectively tune the resonance frequency of such a microwave detector over a wide range up to 43.5 GHz with a potential sensitivity near 2.5 µ V W−1. We confirm the pure spin current nature by changing the polarity of the detected via inverse spin Hall effect voltage by switching the direction of the bias magnetic field. We believe that our results will be useful for the development of highly tunable, portable and sensitive microwave antiferromagnet-based functional devices. [ABSTRACT FROM AUTHOR]

We study both theoretically and experimentally the interaction of surface elastic waves with 2D surface phononic crystal (PnC) on a piezoelectric substrate. A rigorous analysis based on 3D finite element method is conducted to calculate the band structure of the PnC and to analyze the transmission spectrum (module and phase). Interdigital transducers (IDTs) are considered for electrical excitation and detection, and absorbing boundary conditions are used to suppress wave's reflection from the edges. The PnCs are composed of an array of 20 Nickel cylindrical pillars arranged in a square lattice symmetry, and deposited on a LiNbO3 substrate (128°Y cut-X propagating) between two dispersive IDTs. We investigate by means of band diagrams and transmission spectrum the opening band-gaps originating from pillars resonant modes and from Bragg band-gap. The physical parameters that influence and determine their appearance are also discussed. Experimental validation is achieved through electrical measurement of the transmission characteristics, including amplitude and phase. [ABSTRACT FROM AUTHOR]

In the present paper, giant magnetostrictive (GMS) thin films have been investigated for future microelectromechanical systems (MEMS) purposes. To this end, flexural and torsional motions have been studied in low-field anisotropic GMS single-domain state (SDS) exchange-coupled TbFe-FeCo multilayers (ECML). The magnetoelastic (ME) coefficient [b.sup.[gamma],2] depends strongly on the ECML structures, compositions, and sputtering deposition parameters. GMS multilayers with a high [b.sup.[gamma],2]] (18 MPa for Tb[Fe.sub.2]/[Fe.sub.0.6][Co.sub.0.4] compared to 11 MPa for Tb[Fe.sub.2]/Fe) were obtained with or without an in-plane easy axis with a controlled direction, and without any annealing postprocess. Dynamical excitations of the actuators have been investigated under various conditions. An enhancement up to a factor 5 of the oscillations compared to the TbFe-Fe muitilayers is observed with the possibility to tune the flexural/torsional dynamical behavior of these cantilevers. The corresponding very large dynamical ME susceptibility of these improved uniaxial ECML gives the possibility to control GMS MEMS with further reduction of the excitation field down to a few oersteds. Index Terms--Actuators, dynamics, giant magnetostriction (GMS), multilayer, spin reorientation transition (SRT), thin films.

Giant-magnetostriction (GMS) reported in exchange-coupled multilayers (ECML) present quasi-isotropic magnetostrictive behavior. The study presented shows the possibility to induce highly anisotropic GMS at low field with the single domain state in (TbFe/Fe)(sub n) multilayers when deposited by ion sputtering under a magnetic polarization field H(sub d).