JOINUS: A User-Friendly Open-Source Software to Simulate Digital Superconductor Circuits

Single-flux-quantum-based circuits are the subjects of renewed attention due to their high speed and very high energy efficiency. However, the need of cryogenic temperature, the complex physics of Josephson junctions, and the lack of proper electronic design automation (EDA) tools causes slow progress in the field of superconducting electronics. In this article, we introduce a new open-source program named JOsephson INterface Utility Software (JOINUS) that incorporates simulation program with integrated circuit emphasis (SPICE)-based simulator engines, improved physical models, and several powerful built-in routines. JOINUS is based on a user-friendly environment available on Linux, MacOS, and Windows platforms to simplify the design and analysis of superconducting digital circuits.