Griffiths phase in diluted magnetic semiconductors

被引：63

作者：

Galitski, VM ^{[1
]}

Kaminski, A ^{[1
]}

Das Sarma, S ^{[1
]}

机构：

[1] Univ Maryland, Dept Phys, Condensed Matter Theory Ctr, College Pk, MD 20742 USA

来源：

PHYSICAL REVIEW LETTERS | 2004年 / 92卷 / 17期

关键词：

D O I：

10.1103/PhysRevLett.92.177203

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We study the effects of disorder in the vicinity of the ferromagnetic transition in a diluted magnetic semiconductor in the strongly localized regime. We derive an effective polaron Hamiltonian, which leads to the Griffiths phase above the ferromagnetic transition point. The Griffiths-McCoy effects yield nonperturbative contributions to the dynamic susceptibility. We explicitly derive the long-time susceptibility, which has a pseudoscaling form, with the dynamic critical exponent being expressed through the percolation indices.

引用

页码：177203 / 1

页数：4

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