Advances in Josephson Junction Materials and Processes Toward Practical Quantum Computing

TL;DR

This review discusses recent advances in Josephson junction materials and fabrication techniques that are critical for scaling superconducting quantum technologies to practical, industrial-scale quantum computers.

Contribution

It surveys progress in materials science, device characterization, and nanofabrication that address key challenges in developing next-generation Josephson junctions.

Findings

Advances in materials and fabrication improve junction reproducibility and low dissipation.

Emerging junction materials and foundry-compatible processes are being integrated.

Progress will accelerate the transition from laboratory to industrial quantum processors.

Abstract

The Josephson junction is the fundamental nonlinear building block of superconducting quantum technologies. Its macroscopic quantum tunneling physics underpins superconducting quantum computing, sensing, and communication, but scaling these platforms to utility-scale architectures places increasingly stringent demands on junction materials, interfaces, and fabrication. In quantum computing, these demands include high reproducibility, low dissipation, tunability, compact device footprint, and resilience to noise and defects. This review surveys how advances in materials science, device characterization, and nanofabrication are addressing these challenges and redefining the figures of merit for next-generation Josephson junctions. We also examine the evolution of fabrication strategies, from conventional multi-angle evaporation to foundry-compatible superconducting processes and the integration of emerging junction materials. Progress along these directions will determine how rapidly Josephson junctions move from laboratory-scale components to the foundation of industrial-scale quantum processors.