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arXiv · 2301.00456

Characteristic lengthscales of the electrically-induced insulator-to-metal transition

Theodor Luibrand·Adrien Bercher·Rodolfo Rocco·Farnaz Tahouni-Bonab·Lucia Varbaro·Carl Willem Rischau·Claribel Domínguez·Yixi Zhou·Weiwei Luo·Soumen Bag·Lorenzo Fratino·Reinhold Kleiner·Stefano Gariglio·Dieter Koelle·Jean-Marc Triscone·Marcelo J. Rozenberg·Alexey B. Kuzmenko·Stefan Guénon·Javier del Valle
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Abstract

Some correlated materials display an insulator-to-metal transition as the temperature is increased. In most cases this transition can also be induced electrically, resulting in volatile resistive switching due to the formation of a conducting filament. While this phenomenon has attracted much attention due to potential applications, many fundamental questions remain unaddressed. One of them is its characteristic lengths: what sets the size of these filaments, and how does this impact resistive switching properties. Here we use a combination of wide-field and scattering-type scanning near-field optical microscopies to characterize filament formation in NdNiO3 and SmNiO3 thin films. We find a clear trend: smaller filaments increase the current density, yielding sharper switching and a larger resistive drop. With the aid of numerical simulations, we discuss the parameters controlling the filament width and, hence, the switching properties.

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Theodor Luibrand, Adrien Bercher, Rodolfo Rocco, Farnaz Tahouni-Bonab, Lucia Varbaro, Carl Willem Rischau, Claribel Domínguez, Yixi Zhou, Weiwei Luo, Soumen Bag, Lorenzo Fratino, Reinhold Kleiner, Stefano Gariglio, Dieter Koelle, Jean-Marc Triscone, Marcelo J. Rozenberg, Alexey B. Kuzmenko, Stefan Guénon, Javier del Valle. 2023-01-01. Characteristic lengthscales of the electrically-induced insulator-to-metal transition. https://arxiv.org/abs/2301.00456

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