The chemical control of colossal magnetoresistance (CMR) in the new two-dimensional La-1.2(Sr1.8-xCax)Mn2O7 system

Authors
Liu, RS Shen, CH Lin, JG Chen, JM Liu, RG Huang, CY
Citation
Rs. Liu et al., The chemical control of colossal magnetoresistance (CMR) in the new two-dimensional La-1.2(Sr1.8-xCax)Mn2O7 system, INT J INORG, 1(1), 1999, pp. 61-65
Citations number
17
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
INTERNATIONAL JOURNAL OF INORGANIC MATERIALS
ISSN journal
14666049 → ACNP
Volume
1
Issue
1
Year of publication
1999
Pages
61 - 65
Database
ISI
SICI code
1466-6049(199904)1:1<61:TCCOCM>2.0.ZU;2-R
Abstract
The magnetic and electrical properties of the colossal magnetoresistance (C MR) La-1.2(Sr1.8-xCax)Mn2O7 materials have been investigated. Based on the chemical titration method, the valence of Mn was determined to be 3.39+/-0. 04 for all measured La-1.2(Sr1.8-xCax)Mn2O7. The magnetoresistance ratio [r ho(0)/p(H)] was efficiently increased from similar to 192% (135 K, 1.5 T) f or x = 0 to 208% (102 K, 1.5 T) for x = 0.4 in La-1.2(Sr1.8-xCax)Mn2O7. Mor eover, the Curie temperature (T-c) decreased with increasing x and was stro ngly dependent on the apical bond lengths of Mn-O(2). (C) 1999 Elsevier Sci ence Ltd. All rights reserved.