Transport-magnetism correlations in the ferromagnetic oxide La0.7Ca0.3MnO3

• DOI: 10.1063/1.115529
• Publication Date: 2002-07-26T13:40:46Z
• Authors: M. F. Hundley; M. Hawley; R. H. Heffner; Q. X. Jia; J. J. Neumeier; J. Tesmer; J. D. Thompson; X. D. Wu
• Keywords: Magnetism; Colossal Magnetoresistance; Pulsed Laser Deposition

We present results of temperature and magnetic field dependent resistivity ρ(H,T) bulk magnetization M(H,T) measurements on post-annealed La0.7Ca0.3MnO3 thin films that were grown via pulsed-laser deposition. Both the anomalously large negative magnetoresistance peak near ferromagnetic ordering (Tc=250 K), with Δρ/ρ0=−85% at 50 kOe. A clear correlation is found between ρ M described by phenomenological expression ρ(H,T)∝exp[−M(H,T)/M0]. This reflects important interplay transport magnetism in this system, suggests below Tc involves polaron hopping.