ナノ構造磁性体における磁壁ダイナミックスの理論

摘要

Current-induced domain-wall motion in nanostructured ferromagnets has theoretically been studied.Based on fundamental conservation laws spin transfer torque and spin motive force were derived.These new concepts have renewed the long-standing study of domain-wall motion. We also introduce collective coordinate models that offer a minimum but comprehensive framework for understanding various experimental observations. The essential differences between field- and current-induced domain-wall motion are discussed in light of an appropriate damping model.The models are then extended to address recent experiments in which the inhomogeneous nature of the nanostructures affects the dynamics of domain walls.