This article is cited in 13 papers

Phase transitions

Influence of grain boundaries on resistivity of manganites La$_{1-x}$K$_x$MnO$_3$

A.G. Gamzatov^a, A. B. Batdalov^a, L. N. Khanov^a, A. S. Mankevich^b, I. E. Korsakov^b, A. R. Kaul<sup>b

a</sup> Daghestan Institute of Physics after Amirkhanov
^b Lomonosov Moscow State University

Abstract: Results of investigation of resistivity and magnetoresistance of manganites La$_{1-x}$K$_x$MnO$_3$ ($x$ = 0.050–0.175) are presented. Behavior of resistivity $\rho(T)$ in the paramagnetic and ferromagnetic phases has been described. To describe $\rho(T)$ near the phase-transition temperature, notions of the percolation theory have been used. Two maxima have been found in the dependence $\rho(T)$; their appearance has been attributed to the ceramic nature of the studied samples. The observed increase in magnetoresistance with a decrease in temperature is caused by intergranular spin-polarized tunneling of charge carriers.

Received: 12.07.2011

 English version: Physics of the Solid State, 2012, 54:3, 617–621

Bibliographic databases:

•