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arXiv · 1907.00224

Observation of anomalous non-Ohmic transport in current-driven nanostructures

Guanxiong Chen·Ryan Freeman·Andrei Zholud·Sergei Urazhdin
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Abstract

Sufficiently large electric current applied to metallic nanostructures can bring them far out-of-equilibrium, resulting in non-Ohmic behaviors characterized by current-dependent resistance. We experimentally demonstrate a linear dependence of resistance on current in microscopic thin-film metallic wires at cryogenic temperatures, and show that our results are inconsistent with common non-Ohmic mechanisms such as Joule heating. As the temperature is increased, the linear dependence becomes smoothed out, resulting in the crossover to behaviors consistent with Joule heating. A plausible explanation for the observed behaviors is the strongly non-equilibrium distribution of phonons generated by the current. Analysis based on this interpretation suggests that the observed anomalous current-dependent resistance can provide information about phonon transport and electron-phonon interaction at nanoscale. The ability to control the properties of phonons generated by current can lead to new routes for the optimization of thermal properties of electronic nanodevices.

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Guanxiong Chen, Ryan Freeman, Andrei Zholud, Sergei Urazhdin. 2019-06-29. Observation of anomalous non-Ohmic transport in current-driven nanostructures. https://doi.org/10.1103/physrevx.10.011064

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