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arXiv · 1404.7669

Probing near-interface ferroelectricity by conductance modulation of a nano-granular metal

Michael Huth·Achim Rippert·Roland Sachser·Lukas Keller
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Abstract

The electronic functionality of thin films is governed by their interfaces. This is very important for the ferroelectric (FE) state which depends on thin-film clamping and interfacial charge transfer. Here we show that in a heterostructure consisting of a nano-granular metal and an organic FE layer of [tetrathiafulvalene]$^{+δ}$[p-chloranil]$^{-δ}$ the nano-granular layer's conductance provides a sensitive and non-invasive probe of the temperature-dependent dielectric properties of the FE layer. We provide a theoretical framework that is able to qualitatively reproduce the observed conductance changes taking the anisotropy of the dielectric anomaly at the paraelectric(PE)-FE phase transition into account. The approach is also suitable for observing dynamical effects close to the phase transition. Focused electron beam induced deposition as fabrication method for the nano-granular metal guarantees excellent down-scaling capabilities, so that monitoring the FE state on the lateral scale down to 20--30\,nm can be envisioned.

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Michael Huth, Achim Rippert, Roland Sachser, Lukas Keller. 2014-04-30. Probing near-interface ferroelectricity by conductance modulation of a nano-granular metal. https://doi.org/10.1088/2053-1591%2F1%2F4%2F046303

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