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arXiv · 1006.3162

Reduction of low-frequency 1/f noise in Al-AlOx-Al tunnel junctions by thermal annealing

Juhani Julin·Panu Koppinen·Ilari Maasilta
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Abstract

We report that annealing Al-AlOx-Al tunnel junctions in a vacuum chamber at temperature of 400C reduces the characteristic 1/f noise in the junctions, in some cases by an order of magnitude. Both ultra high vacuum and high vacuum fabricated samples demonstrated a significant reduction in the 1/f noise level. Temperature dependence of the noise was studied between 4.2 and 340 Kelvin, with a linear dependence below 100 K, but a faster increase above. The results are consistent with a model where the density of charge trapping two level-systems within the tunneling barrier is reduced by the annealing process.

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Juhani Julin, Panu Koppinen, Ilari Maasilta. 2010-10-07. Reduction of low-frequency 1/f noise in Al-AlOx-Al tunnel junctions by thermal annealing. https://doi.org/10.1063/1.3500823

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