A. Ruthenates C. Grain boundary D. Fractal D. Percolation Electric conductivity Mathematical models Numerical analysis Percolation (fluids)
Issue Date:
2006
Publisher:
Solid State Communications
Citation:
Volume: 139, Issue: 9, Page : 456-459
Abstract:
Percolation theory has been involved to explain the temperature dependence of conductivity in the
K-doped perovskite ruthenates and to estimate the resistivity of grain boundary in the percolative conduction
regime. Using the two-layer simple effective medium model [A. Gupta, G.Q. Gong, G. Xiao, P.R.
Duncombe, P. Lecoeur, P. Trouilloud, Y.Y. Wang, V.P. Dravis, J.Z. Sun, Phys. Rev. B 54 (1996) R15629]
and assuming the scaling property of grain boundary system, we have obtained the new formula for grain
boundary resistivity, which contains important factors for the grain size, boundary thickness, and boundary
fractal dimension. The numerical results for the system A0.5K0.5RuO3 (A=La, Y, Nd, Pr) are in very good
agreement with the experiment. Importantly, it reveals that the percolative conduction plays a significant
role in ceramic compounds containing polycrystalline grains and grain boundaries. ?? 2006 Elsevier Ltd. All
rights reserved.
