[ED6] Novel Devices, Materials and Fabrication

10:15 AM - 10:45 AM JST(1:15 AM - 1:45 AM UTC)

[ED6-02-INV] From Weak Links to Quantum Coherence: A Focused Ion Beam Perspective on Superconducting Tunneling Phenomena

*Jay Clayton LeFebvre¹, Shane A. Cybart¹ (1. University of California, Riverside (United States of America))

Keywords:

Focused Ion Beam,Carrier Tunneling,Josephson Junction

Practical implementation of superconducting electronics remains an elusive scientific hurdle. Inspired by the improved 3D integration of finFETs in semiconducting technology, superconductive electronics may be improved through focused ion beam lithography of Josephson junctions. This technique promises advances for superconductive electronics through the reduction of the dimensions of critical components, simultaneously improving design scalability and reducing susceptibility of errors due to trapped flux. Additionally, this approach provides a simplified fabrication process that reduces noisy interfaces. I review recent advances in focused ion beam nanofabrication that improve our scientific and engineering understanding of superconductive electronics. Ion irradiation incident on superconducting materials undergoes a phase transition that can be utilized for lithography of superconductive electronics featuring a tunable barrier with a critical dimension that is of the scale of the superconducting coherence length. This technique directly writes Josephson junctions into thin superconducting films. This planar Josephson junction geometry with carrier transport parallel to the film plane offers novel ways to characterize tunneling mechanisms. Differential conductance measurements taken across these junctions characterize the density of states and barrier quality of this technique. A practical order parameter of superconductivity is defined and used to characterize material performance. I will discuss this methodology’s promising integration into already existing superconductive electronics device processing.