DISSIPATION AND QUANTUM PROPAGATION OF BLOCH WALLS

被引:17
作者
BRAUN, HB
LOSS, D
机构
[1] Department of Physics, Simon Fraser University
来源
EUROPHYSICS LETTERS | 1995年 / 31卷 / 09期
关键词
D O I
10.1209/0295-5075/31/9/009
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
Bloch walls in mesoscopic ferromagnets are shown to tunnel coherently between periodically arranged pinning sites and to form a band similar to a Bloch electron in a crystal lattice. Eliminating the spin wave degrees of freedom we derive an effective action for the Bloch wall position. The dissipative term in this action involves a spectral function with a gap and therefore damping due to spin waves is negligible at low temperatures. It is shown that the Berry phase gives rise to a spin-parity-dependent shift in the dispersion. We show that this band structure can give rise to Bloch oscillations of the magnetization in response to a static external field, which provides a magnetic analog to the Josephson effect.
引用
收藏
页码:555 / 560
页数:6
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