High resolution determination of ferromagnetic metallic limit in epitaxial La1-xCaxMnO3 films on NdGaO3
arXiv:cond-mat/0605187 · doi:10.1063/1.2360211
Abstract
The physical properties of manganites depend strongly on sample morphology, probably due to strain. We investigate the influence of NdGaO3 substrates on the limit of the ferromagnetic-metallic phase field in La1-xCaxMnO3, doping with x=1% resolution. Films with x=0.40 show a metal-insulator transition, but the ferromagnetic volume fraction is half the spin aligned value. Films with x=0.41 are similar but the metal-insulator transition is not always seen. Films with x=0.42, 0.43, 0.44, 0.45 are insulating, and the magnetization is dramatically reduced. The observed phase boundary indicates where to search for enhanced phase separation effects that may be exploited in thin films and devices.