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تسجيل مستخدم جديدNonreciprocal propagation of surface acoustic wave in Ni/LiNbO3
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We have investigated surface acoustic wave propagation in Ni/LiNbO$_3$ hybrid devices. We have found the absorption and phase velocity are dependent on the sign of wave vector in a device, which indicates the nonreciprocal propagation characteristic of systems with time reversal and spatial inversion simultaneously broken symmetries. The nonreciprocity is reversed by the 180$^circ$ rotation of magnetic field. Nonreciprocity seems largely dependent on the shape of ferromagnetic Ni film. The origin of these observations is ascribed to film shape dependent magnetoelastic coupling.
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