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Out of equilibrium electronic transport properties of a misfit cobaltite thin film

A. Pautrat·H. W Eng·W. Prellier
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Abstract

We report on transport measurements in a thin film of the 2D misfit Cobaltite $Ca_{3}Co_{4}O_{9}$. Dc magnetoresistance measurements obey the modified variable range hopping law expected for a soft Coulomb gap. When the sample is cooled down, we observe large telegraphic-like fluctuations. At low temperature, these slow fluctuations have non Gaussian statistics, and are stable under a large magnetic field. These results suggest that the low temperature state is a glassy electronic state. Resistance relaxation and memory effects of pure magnetic origin are also observed, but without aging phenomena. This indicates that these magnetic effects are not glassy-like and are not directly coupled to the electronic part.

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A. Pautrat, H. W Eng, W. Prellier. 2005-11-02. Out of equilibrium electronic transport properties of a misfit cobaltite thin film. https://doi.org/10.1103/physrevb.72.233405

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