High quality superconducting tunnel junction barriers using atomic layer deposition

Stephanie M. Moyerman; Guangyuan Feng; Lisa Krayer; Nathan Stebor; Brian G. Keating

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arXiv · 1303.6399

High quality superconducting tunnel junction barriers using atomic layer deposition

Stephanie M. Moyerman·Guangyuan Feng·Lisa Krayer·Nathan Stebor·Brian G. Keating

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Abstract

We demonstrate a technique for creating high quality, large area tunnel junction barriers for normal-insulating- superconducting or superconducting-insulating-superconducting tunnel junctions. We use atomic layer depo- sition and an aluminum wetting layer to form a nanometer scale insulating barrier on gold films. Electronic transport measurements confirm that single-particle electron tunneling is the dominant transport mechanism, and the measured current-voltage curves demonstrate the viability of using these devices as self-calibrated, low temperature thermometers with a wide range of tunable parameters. The potential for fabricating high performance junction refrigerators is also highlighted.

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Stephanie M. Moyerman, Guangyuan Feng, Lisa Krayer, Nathan Stebor, Brian G. Keating. 2013-03-26. High quality superconducting tunnel junction barriers using atomic layer deposition. https://arxiv.org/abs/1303.6399

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