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arXiv · 1603.05438

Observing "Quantized" Conductance Steps in Silver Sulfide: Two Parallel Resistive Switching Mechanisms

Abstract

We demonstrate that it is possible to distinguish two conductance switching mechanisms in silver sulfide devices at room temperature. Experiments were performed using a Ag$_2$S thin film deposited on a wide Ag bottom electrode, which was contacted by the Pt tip of a scanning tunneling microscope. By applying a positive voltage on the silver electrode the conductance is seen to switch to a state having three orders of magnitude higher conductance, which is related to the formation of a conductive path inside the Ag$_2$S thin film. We argue this to be composed of a metallic silver nanowire accompanied by a modification of the surrounding lattice structure. Metallic silver nanowires decaying after applying a negative voltage allow observing conductance steps in the breaking traces characteristic for atomic-scale contacts, while the lattice structure deformation is revealed by gradual and continuously decreasing conductance traces.

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J. J. T. Wagenaar, M. Morales-Masis, J. M. van Ruitenbeek. 2016-03-17. Observing "Quantized" Conductance Steps in Silver Sulfide: Two Parallel Resistive Switching Mechanisms. https://doi.org/10.1063/1.3672824

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