Thickness dependent phase separation in La0.7Ca0.3MnO3 films

The complex dielectric function of La0.7Ca0.3MnO3 films with various thicknesses and on different substrates was determined by the analysis of measured ellipsometric parameters. The temperature-dependent redistribution of low-energy spectral weight shows that the metallicity is developed gradually b...

Full description

Saved in:
Bibliographic Details
Published in:Applied physics letters 2002-11, Vol.81 (20), p.3777-3779
Main Authors: Rauer, R., Bäckström, J., Budelmann, D., Kurfiß, M., Schilling, M., Rübhausen, M., Walter, T., Dörr, K., Cooper, S. L.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The complex dielectric function of La0.7Ca0.3MnO3 films with various thicknesses and on different substrates was determined by the analysis of measured ellipsometric parameters. The temperature-dependent redistribution of low-energy spectral weight shows that the metallicity is developed gradually below an onset temperature that is found to depend strongly on global and local strain properties, not on film thickness alone. Importantly, the 2 nm film shows no metallic conduction but an optical charge-carrier response below 240 K. This suggests that ultrathin films are characterized by phase separation and a percolation-type transition.
ISSN:0003-6951
1077-3118
1077-3118
DOI:10.1063/1.1520705