Tunable non-reciprocity of elastic waves in one-dimensional magnetoelastic phononic crystal plate with oblique incident angle

Abstract

In this work, non-reciprocal A0 wave in a one-dimensional (1D) magnetoelastic phononic crystal (PC) plate is observed by adjusting the magnitude of the external static magnetic field and the angle of incidence of the elastic wave. This phenomenon arises from the both breaking of time-reversal and spatial-inversion symmetries. When the angle between the applied in-plane magnetic field and the wave vector direction is greater than 0°, the spin waves exhibit a small non-reciprocity. The non-reciprocal spin waves couples with the elastic wave to form a non-reciprocal bandgap, which is distinct from the asymmetric transmission of elastic waves in non-periodic structures. Our research provides robust way to manipulate the transmission characteristics of A0-Lamb waves and has potential application in the design of diodes in seismic exploration and material testing.