On the Path to High-temperature Josephson Multi-junction Devices

TL;DR

This paper advances high-temperature superconductor Josephson junction technology using helium ion beam damage, enabling high characteristic voltages and complex device designs, bridging the gap with low-temperature superconductor circuits.

Contribution

It introduces a helium ion beam damage technique for fabricating HTS Josephson junctions, allowing high voltage and arbitrary junction placement in a single-layer YBCO film.

Findings

Achieved high characteristic voltage $V_c=I_cR_N$ in HTS Josephson junctions.

Demonstrated the ability to design multiple arbitrary junctions within a single layer.

Proposed a one-layer active electrically small antenna with specific voltage response characteristics.

Abstract

We report our progress in the high-temperature superconductor (HTS) Josephson junction fabrication process founded on using a focused helium ion beam damaging technique and discuss the expected device performance attainable with the HTS multi-junction device technology. Both the achievable high value of characteristic voltage $V_c=I_cR_N$ of Josephson junctions and the ability to design a large number of arbitrary located Josephson junctions allow narrowing the existing gap in design abilities for LTS and HTS circuits even with using a single YBCO film layer. A one-layer topology of active electrically small antenna is suggested and its voltage response characteristics are considered.