Published December 2004 | Version v1
Journal article

Insulator-metal transition and magnetoresistance of oxygen deficient La0.35Ca0.65MnOy

  • 1. Department of Physics, Tsinghua University, Beijing 100084 (China)
  • 2. Center for Superconductivity Research, Department of Physics, University of Maryland, College Park, MD 20742 (United States)
  • 3. Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India)

Description

The oxygen content of La0.35Ca0.65MnOy was decreased by annealing the samples at high temperatures in vacuum with graphite powder nearby. Insulator-metal (I-M) transition occurred upon dramatic decrease of oxygen content. Correspondingly the samples showed a large magnetoresistance (MR) and MR=C(M/Ms)2 at 4.5K up to relatively large M/Ms. The results were explained in terms of the variation of Mn3+/Mn4+ ratio and oxygen vacancy ordering induced percolation of the ferromagnetic regions. Spin-dependent hopping model can account for the variation of MR with M/Ms and the variation of C with the decrease of oxygen content

Additional details

Identifiers

DOI
10.1016/j.jmmm.2004.06.017;
PII
S0304-8853(04)00667-5;

Publishing Information

Journal Title
Journal of Magnetism and Magnetic Materials
Journal Volume
284
Journal Issue
3
Journal Page Range
p. 35-42
ISSN
0304-8853
CODEN
JMMMDC

Optional Information

Copyright
Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.