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arXiv · 1406.7310

Observation of thermally activated glassiness and memory dip in a-NbSi insulating thin films

Julien Delahaye·Thierry Grenet·C. Marrache-Kikuchi·L. Bergé·A. A. Drillien
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Abstract

We present electrical conductance measurements on amorphous NbSi insulating thin films. These films display out-of equilibrium electronic features that are markedly different from what has been reported so far in disordered insulators. Like in the most studied systems (indium oxide and granular Al films), a slow relaxation of the conductance is observed after a quench to liquid helium temperature which gives rise to the growth of a memory dip in MOSFET devices. But unlike in these systems, this memory dip and the related conductance relaxations are still visible up to room temperature, with clear signatures of a temperature dependent dynamics.

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Julien Delahaye, Thierry Grenet, C. Marrache-Kikuchi, L. Bergé, A. A. Drillien. 2014-06-27. Observation of thermally activated glassiness and memory dip in a-NbSi insulating thin films. https://doi.org/10.1209/0295-5075%2F106%2F67006

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