Tension-induced magnetic Barkhausen noise morphology transition caused by pre-introduced strain

Magnetic Barkhausen noise (MBN) technology is widely used to reveal the microscopic mechanism of magnetomechanical phenomena, but the morphological transition induced by tension has not yet been confirmed by experimental measurements. Here, we report a novel effect on the morphology transition of MBN signals due to tensile stress with pre-introduced strain. We present a power-law relation between the critical stress for the morphology transition and the degree of pre-introduced strain, highlighting the strong correlation between plastic deformation and MBN response. Through comprehensive microscopic simulations, we reveal that dislocations localized in regions with distinct densities trigger different MBN avalanches, thereby leading to a bimodal morphology of the MBN signal. Upon reloading, an effective field introduced by stress promotes the realignment of the magnetic domains, thereby resulting in the formation of a unimodal morphology of the MBN signal. Our unprecedented findings provide valuable insights into the correlation between deformation and MBN signal response, thereby opening a new avenue for designing and optimizing ferromagnetic materials with tailored magnetic behavior.