Heating and non-ohmic transport in phase-separated manganites
National Laboratory of Solid State Microstructures
and Department of Physics, Nanjing University, Nanjing 210093, P.R.
2 Department of Physics, Henan Normal University, Xinxiang 453007, P.R. China
Corresponding author: a firstname.lastname@example.org
Published online: 8 August 2005
We investigate the features of non-ohmic transport in phase-separated manganites by Monte Carlo simulations in a random network with clusters of ferromagnetic metal and antiferromagnetic insulator. It is found that, by taking into account the heating process and the temperature dependence of resistivity, the current-voltage characteristics are highly non-ohmic and exhibit hysteresis in sweeping the voltage. We calculate the temperature dependence of this behavior, and investigate the changes of the percolative paths at different currents. The breakdown of most percolative paths by the heating effect of the current results in an interrupt transition from the metallic behavior to the insulator behavior of the system. The obtained results are in good agreement with related experiments.
PACS: 75.40.Mg – Numerical simulation studies / 75.50.-y – Studies of specific magnetic materials / 64.60.Ak – Renormalization-group, fractal, and percolation studies of phase transitions / 64.75.+g – Solubility, segregation, and mixing; phase separation
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005