Chirality tunneling and quantum dynamics for domain walls in mesoscopic ferromagnets

作     者：E. G. Galkina B. A. Ivanov Sergey Savel’ev Franco Nori 

作者机构：Frontier Research System The Institute of Physical and Chemical Research (RIKEN) Wako-shi Saitama 351-0198 Japan Institute of Physics 03028 Kiev Ukraine Institute of Magnetism 03142 Kiev Ukraine Department of Physics Loughborough University Leicestershire LE11 3TU United Kingdom Department of Physics Center for Theoretical Physics Applied Physics Program Center for the Study of Complex Systems University of Michigan Ann Arbor Michigan 48109-1040 USA 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2008年第77卷第13期

页      面：134425-134425页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：National Science Foundation, NSF, (0130383) Engineering and Physical Sciences Research Council, EPSRC, (EP/D072581/1) 

摘      要：We studied the quantum dynamics of ferromagnetic domain walls (topological kink-type solitons) in one-dimensional ferromagnetic spin chains. We show that the tunneling probability does not depend on the number of spins in a domain wall; thus, this probability can be large even for a domain wall containing a large number of spins. We also predict that there is a strong interplay between the tunneling of a wall from one lattice site to another (tunneling of the kink coordinate) and the tunneling of the kink topological charge (so-called chirality). Both of these elementary processes are suppressed for kinks in one-dimensional ferromagnets with half-integer spin. The dispersion law (i.e., the domain wall energy versus momentum) is essentially different for chains with either integer or half-integer spins. The predicted quantum effects could be observed for mesoscopic magnetic structures, e.g., chains of magnetic clusters, large-spin molecules, or nanosize magnetic dots.