%0 Journal Article
%K thin films
%K Perovskite
%K oxides
%K manganese compounds
%K Epitaxial growth
%K superlattices
%K Magnetic field effects
%K Magnetic films
%K Electric conductivity measurement
%K Epitaxial magnetoresistive films
%K Giant magnetoresistance increase
%K Laser-ablated oxide films
%K Manganese oxide magnetic films
%K Perovskite magnetic films
%K Superlattice magnetic films
%A S Jin
%A T.H Tiefel
%A M McCormack
%A R.A Fastnacht
%A Ramamoorthy Ramesh
%A L.H Chen
%B Science
%D 1994
%G eng
%P 413-415
%R 10.1126/science.264.5157.413
%T Thousandfold change in resistivity in magnetoresistive La-Ca-Mn-O films
%V 264
%X A negative isotropic magnetoresistance effect more than three orders of magnitude larger than the typical giant magnetoresistance of some superlattice films has been observed in thin oxide films of perovskite-like La 0.67Ca0.33MnOx. Epitaxial films that are grown on LaAlO3 substrates by laser ablation and suitably heat treated exhibit magnetoresistance values as high as 127,000 percent near 77 kelvin and ∼1300 percent near room temperature. Such a phenomenon could be useful for various magnetic and electric device applications if the observed effects of material processing are optimized. Possible mechanisms for the observed effect are discussed.