Direct relationship of chiral spin texture induced variations of system energy and magnetization switching

Since the chirality by the inversion symmetry breaking has been observed, systems influenced by the Dzyaloshinskii-Moriya interaction (DMI) induced chirality were actively investigated. Here, diverse reports proves that the chirality affects to the dynamic and static characteristics of spin phenomena, the magnetization switching is also no exception. However, previous findings about chirality-dependent magnetization switching just confirmed its possibility phenomenologically without consideration of presence of a deeper mechanism.

In this report, we show that the chirality-dependent magnetization switching, in field- and spin-orbit torque (SOT)-induced both, is originated by the system energy variation, which is proved in theoretically and experimentally. A theoretical model is derived from the Hamiltonian including DMI and our experimental results of field-induced switching are well explained by the theoretical model, implying direct relationship between chirality and field-induced magnetization switching. As a next step, we directly compared chirality-dependent field-switching and SOT-switching, the results show clear correlation. Therefore, we can propose the chiral-dependent energy variation as the common origin in both of chirality-dependent field- and SOT-induced switching.