A Practical Open-Source Software Stack for a Cloud-Based Quantum Computing System

TL;DR

This paper introduces OQTOPUS, an open-source, full-stack software system for cloud-based quantum computing, enabling easier access, operation, and development of quantum computers with real-world experimental validation.

Contribution

It presents OQTOPUS, a comprehensive open-source quantum computing software stack, including key features like transpilers and error mitigation, developed from real quantum computer research.

Findings

Successful application of OQTOPUS to a real quantum computer

Open-source availability on GitHub facilitates community engagement

Lowered barriers to entry in quantum computing development

Abstract

Since the late 2010s, quantum computers have become commercially available, and the number of services that users can run remotely via cloud servers is increasing. In Japan, several domestic superconducting quantum computing systems, including our own, began operation in 2023. However, the design of quantum computing systems, especially in the most critical areas near quantum computers, remains largely undisclosed, creating a significant barrier to entry into the quantum computing field. If this situation continues, progress toward standardization, which is essential for guiding quantum computer development, will stall, and it will be difficult to develop a practical quantum computing system that can perform calculations on a supercomputer scale. To address this issue, we propose Open Quantum Toolchain for OPerators and USers (OQTOPUS), a full-stack quantum computing system developed from research with real quantum computers. OQTOPUS is one of the world's largest open-source software projects, covering operational software from cloud-based execution environment construction to system operation. Furthermore, to perform quantum computing effectively and efficiently, it implements key features, such as transpilers, multiprogramming, and error mitigation, in an area as close as possible to a quantum computer, an area that system vendors rarely disclose. Finally, this study presents experimental results of applying OQTOPUS to a real quantum computer. OQTOPUS is publicly available on GitHub and will notably lower the barrier to entry into the quantum computing field, contributing to the formation of a quantum computing developer community through open discussion.