Influence of measurement field on the magnetic domains for zero-field cooling exchange bias effect in Ni₅₀Mn₃₇Ga₁₃ alloy

The exchange bias effect obtained after zero field cooling (ZEB) not only saves energy but also makes the device easier to control and reduces the size of the device. In this work, the ZEB effect under different measurement fields is obtained in Ni₅₀Mn₃₇Ga₁₃ alloy, further, combining the macroscopic magnetic test and phase field simulation, the microscopic magnetic states under different measurement fields are studied. Through phase field simulation, it is revealed that the density of the ferromagnetic (FM)/antiferromagnetic (AFM) interface first expands and then shrinks with the increase of measurement field, which thus explains the optimum ZEB at an intermediate measurement field. This work reveals the important role of the FM/AFM interface in the ZEB effect.