Strain-Enhanced Colossal Magnetoresistance in Pr0.6Sr0.4MnO3 Thin Films

Abstract

Thin films of Pr0.6Sr0.4MnO3 have been prepared on (100)-oriented single crystalline SrTiO3 and LaAlO3 substrates using pulsed laser deposition. X-ray diffraction analysis reveals formation of thin films with c-axis orientation. The magnetotransport properties of the thin films have been studied in comparison to the polycrystalline bulk sample. Thin films exhibit substantially larger colossal magnetoresistance than the bulk, and the effect is observed to be more pronounced in the film which experiences a larger strain. The resistivity behavior above the metal-insulator transition temperature for the bulk as well as thin films samples follows adiabatic small polaron hopping mechanism for conduction. On the other hand, resistivity in the low-temperature metallic region could be explained considering the electron-magnon and electron-electron scattering contributions to resistivity.