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arXiv · 2308.06240

Superconducting nitridized-aluminum thin films

Alba Torras-Coloma·Leyre Martínez de Olcoz·Eva Céspedes·Elia Bertoldo·David López-Núñez·Sagar Paul·Wolfgang Wernsdorfer·Gemma Rius·Pol Forn-Díaz
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Abstract

We report the direct observation of superconductivity in nitridized-aluminum thin films. The films are produced by sputtering deposition of aluminum in a controlled mixture of nitrogen diluted in argon. The concentration of applied nitrogen directly determines the properties of the superconducting thin films. We observe samples displaying critical temperatures up to 3.38$\pm$0.01K and resilience to in-plane magnetic fields well above 1T, with good reproducibility of the results. This work represents an unambiguous demonstration of tunable superconductivity in aluminum-based nitridized thin films. Our results put forward nitridized aluminum as a promising material to be employed in superconducting quantum circuits for quantum technology applications.

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Alba Torras-Coloma, Leyre Martínez de Olcoz, Eva Céspedes, Elia Bertoldo, David López-Núñez, Sagar Paul, Wolfgang Wernsdorfer, Gemma Rius, Pol Forn-Díaz. 2023-08-11. Superconducting nitridized-aluminum thin films. https://doi.org/10.1088/1361-6668/ad20fc

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