2-SPIN MODEL FOR MACROSCOPIC QUANTUM COHERENCE IN SMALL ANTIFERROMAGNETIC PARTICLES

被引：9
作者：
DUAN, JM
GARG, A
机构：
[1] Department of Physics and Astronomy, Northwestern University, Evanston
来源：
PHYSICA B | 1994年 / 194卷
基金：
美国国家科学基金会;
关键词：
D O I：
10.1016/0921-4526(94)90491-X
中图分类号：
O469 [凝聚态物理学];
学科分类号：
070205 ;
摘要：
We develop a model for studying MQC in small antiferromagnetic particles in terms of two spins representing the total moment on two sublattices. The model can treat external magnetic fields and unequal sublattice moments, and is specifically designed to capture topological effects arising from the Berry phase in the spin action. The tunneling rate is calculated for several configurations; both the usual WKB exponent and the topological term depend on both the field and excess moment.
引用
收藏
页码：323 / 324
页数：2
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