Persistent X-ray photoconductivity and percolation of metallic clusters in charge-ordered manganites

被引：20

作者：

Casa, D ^{[1
]}

Kiryukhin, V

Saleh, OA

Keimer, B

Hill, JP

Tomioka, Y

Tokura, Y

机构：

[1] Princeton Univ, Dept Phys, Princeton, NJ 08544 USA

[2] Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany

[3] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA

[4] Joint Res Ctr Atom Technol, Ibaraki, Osaka 305, Japan

[5] Univ Tokyo, Dept Appl Phys, Tokyo 113, Japan

来源：

EUROPHYSICS LETTERS | 1999年 / 47卷 / 01期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1209/epl/i1999-00356-y

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Charge-ordered manganites of composition Pr1 - x (Ca1 - ySry)(x)MnO3 exhibit persistent photoconductivity upon exposure to X-rays. This is not always accompanied by a significant increase in the number of conduction electrons as predicted by conventional models of persistent photoconductivity. An analysis of the X-ray diffraction patterns and current-voltage characteristics shows that X-ray illumination results in a microscopically phase-separated state in which charge-ordered insulating regions provide barriers against charge transport between metallic clusters. The dominant effect of X-ray illumination is to enhance the electron mobility by lowering or removing these barriers. A mechanism based on magnetic degrees of freedom is proposed.

引用

页码：90 / 96

页数：7

共 10 条

[1] Current switching of resistive states in magnetoresistive manganites [J].