Transport properties of microstructured ultrathin films of La0.67Ca0.33MnO3 on SrTiO3

Abstract

We have investigated the electrical transport properties of 8 nm thick La0.67Ca0.33MnO3 films, sputter-deposited on SrTiO3 (STO), and etched into 5 micrometer-wide bridges by Ar-ion etching. We find that even slight overetching of the film leads to conductance of the STO substrate, and asymmetric and non-linear current-voltage (I-V) characteristics. However, a brief oxygen plasma etch allows full recovery of the insulating character of the substrate. The I-V characteristics of the bridges are then fully linear over a large range of current densities. We find colossal magnetoresistance properties typical for strained LCMO on STO but no signature of non-linear effects (so-called electroresistance) connected to electronic inhomogeneites. In the metallic state below 150 K, the highest current densities lead to heating effects and non-linear I-V characteristics.

arXiv comment3 pages, 5 figures

References in corpus (4)

• Hysteretic current-voltage characteristics and resistance switching at a rectifying Ti/Pr${}_{0.7}$Ca${}_{0.3}$MnO${}_3$ interface
• Two-phase behavior in strained thin films of hole-doped manganites
• Universal behavior of giant electroresistance in epitaxial La0.67Ca0.33MnO3 thin films
• Current-induced metallic behavior in Pr${}_{0.5}$Ca${}_{0.5}$MnO${}_3$ thin films: competition between Joule heating and nonlinear conduction mechanism

Cited by in corpus (3)

• Mesoscopic transport in ultrathin films of La${}_{0.67}$Ca${}_{0.33}$MnO${}_3$
• Metal-insulator transition and electroresistance in lanthanum/calcium manganites La_<1-x>Ca_<x>MnO_<3> (x = 0-0.5) from voltage-current-temperature surfaces
• Large electric field effects on the resistance of La${}_{0.67}$Ca${}_{0.33}$MnO${}_3$ microstructures