Description
The Josephson junction is the fundamental building block of superconducting circuits. Although critically important, its manufacture has proved highly variable, resulting in large distributions of circuit parameters due to the stochastic nature of the deposition process and material disorder. The recent discovery of the alternating bias-assisted annealing method has reintroduced interest in the area, as it provides a post fabrication treatment which reduces variability. Applying this treatment reduces the initially distribution of resistances observed across a wafer into a well-defined and narrower distribution.
Despite this improvement, many questions still remain including what exact mechanisms or defects these annealing methods are optimizing. In this work we investigate how deposition species, temperature, sputtering, multiple grains, and different surfaces affect the transport properties of a Josephson junction. We explore these through an in-house deposition software package that interfaces to the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS), allowing for greater control in the distributions describing the deposited atoms. Using this approach, we can explore options for process optimisation that can then be tested experimentally.
| I am the presenting author | Yes |
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