Atomic Layer Deposition of Tunnel Barriers for Superconducting Tunnel Junctions
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 deposition 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. This work represents a promising first step for superconducting technologies with deposited tunnel junction barriers. The potential for fabricating high performance junction refrigerators is also highlighted.
KeywordsSuperconducting tunnel junctions Atomic layer deposition Tunnel barriers
The authors would like to acknowledge the help and useful discussion from Joel Ullom and Peter Lowell at the National Institute of Standards and Technology in Boulder, Co. S.M. would like to acknowledge the American Association of University Women for fellowship funding.
- 17.Elliot A, Malek G, Wille L, Lu R, Han S, Wu J, Talvacchio J, Lewis R, IEEE Trans. Appl. Supercond. 99 (2013) (in press)Google Scholar