Fluctuation-induced hopping and spin-polaron transport

被引：12
作者：
Wegener, LGL [1 ]
Littlewood, PB [1 ]
机构：
[1] Univ Cambridge, Cavendish Lab, TCM, Cambridge CB3 0HE, England
来源：
PHYSICAL REVIEW B | 2002年 / 66卷 / 22期
关键词：
D O I：
10.1103/PhysRevB.66.224402
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
We study the motion of free magnetic polarons in a paramagnetic background of fluctuating local moments. The polaron can tunnel only to nearby regions of local moments when these fluctuate into alignment. We propose this fluctuation-induced hopping as a transport mechanism for the spin polaron. We calculate the diffusion constant for fluctuation-induced hopping from the rate at which local moments fluctuate into alignment. The electrical resistivity is then obtained via the Einstein relation. We suggest that the proposed transport mechanism is relevant in the high-temperature phase of the Mn pyrochlore "colossal magnetoresistance" compounds and EuB6.
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页码：1 / 8
页数：8
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