EPR evidence of Jahn-Teller polaron formation in La1-xCaxMnO3+y

被引：231

作者：

Shengelaya, A

Zhao, GM

Keller, H

Muller, KA

机构：

[1] Physik-Institut der Universität Zürich, Zürich

来源：

PHYSICAL REVIEW LETTERS | 1996年 / 77卷 / 26期

关键词：

D O I：

10.1103/PhysRevLett.77.5296

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The electron paramagnetic resonance (EPR) signal in the mixed valence perovskite La1-xCaxMnO3+y was investigated in the paramagnetic regime for O-16 and O-18 isotope substituted compounds. The characteristic differences observed in EPR intensity and linewidth for the two isotope samples can be explained by a model in which a bottlenecked spin relaxation takes place from the exchange-coupled constituent Mn4+ ions via the Mn3+ Jahn-Teller ions to the lattice. For x = 0.2 the ferromagnetic exchange energy J exhibits a O-16/O-18 oxygen isotope effect of similar to -10%. The observed isotope effects suggest the presence of Jahn-Teller polarons in these materials.

引用

页码：5296 / 5299

页数：4

共 17 条

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