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arXiv · 1402.6845

Nonlinear conductivity in CaRuO3 thin films measured by short current pulses

Sven Esser·Sebastian Esser·Christian Stingl·Philipp Gegenwart
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Abstract

Metals near quantum critical points have been predicted to display universal out-of equilibrium behavior in the steady current-carrying state. We have studied the non-linear conductivity of high-quality CaRuO$_3$ thin films with residual resistivity ratio up to 57 using micro-second short, high-field current pulses at low temperatures. Even for the shortest pulses of $5\mu$s, Joule heating persists, making it impossible to observe a possible universal non-linearity. Much shorter pulses are needed for the investigation of universal non-linear conductivity.

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Sven Esser, Sebastian Esser, Christian Stingl, Philipp Gegenwart. 2014-02-27. Nonlinear conductivity in CaRuO3 thin films measured by short current pulses. https://doi.org/10.1140/epjb/e2014-50215-1

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