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arXiv · 1207.0970

Kondo-like behavior near the metal-to-insulator transition of nano-scale granular aluminum

N. Bachar·S. Lerer·S. Hacohen-Gourgy·B. Almog·G. Deutscher
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Abstract

We show that the normal state transport properties of nano-scale granular Aluminum films, near the metal to insulator transition, present striking similarities with those of Kondo systems. Those include a negative magneto-resistance, a minimum of resistance R at a temperature Tm in metallic films, a logarithmic rise at low temperatures and a negative curvature of R(T) at high temperatures. These normal state properties are interpreted in terms of spin-flip scattering of conduction electrons by local magnetic moments, possibly located at the metal/oxide interfaces. Their co-existence with the enhanced superconductivity seen in these films is discussed.

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N. Bachar, S. Lerer, S. Hacohen-Gourgy, B. Almog, G. Deutscher. 2012-07-04. Kondo-like behavior near the metal-to-insulator transition of nano-scale granular aluminum. https://doi.org/10.1103/physrevb.87.214512

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