Development of Constructing and Operating Technologies for Quantum-HPC Hybrid Platform

Recently, we have been hearing more and more news about quantum computers. In fact, the number of qubits is increasing year by year, and practical applications have already started in specific fields.

What comes to mind when you think of quantum computers? Some might have a vague image of a dream computer that can do anything. However, that is not the case. Quantum computers are expected to perform faster calculations than conventional computers in areas where they excel, but they cannot replace current computers entirely.

Therefore, it is essential to use both types of computers effectively. Until now, it has been mainstream to develop separate applications for quantum computers and conventional computers. What can be achieved by using these two simultaneously? This field still needs more research, and there currently needs to be an environment to conduct such research.
In this project, we will build an environment where quantum computers and supercomputers are connected and can be used simultaneously. On this platform, users can run applications that consist of Quantum-HPC hybrid programs. This process involves many challenges. Quantum computers differ significantly from conventional computers' mechanisms, including chips, operations, cooling systems, etc. The know-how required for installation, setup, and operation is entirely new. There are also many considerations for the system, such as network connections, user authentication, management, and job execution methods.

The following systems will be connected in the Quantum-HPC Hybrid Platform.

- Supercomputer Fugaku (Kobe)
- Supercomputer for quantum simulation (Kobe, To be installed)
- Superconducting quantum computer (Kobe, To be installed)
- Ion trap quantum computer (Wako, To be installed)
- The University of Tokyo's supercomputer (Tokyo)
- Osaka University's supercomputer (Osaka)

We will start by setting up the physical environment for the three systems to be installed in this project, including building renovations, installation, and operational testing.

All systems will be connected via wide networks, using SINET provided by NII for inter-district connections and high bandwidth, low latency network connections such as InfiniBand for intra-district (Kobe) systems to enable tight integration.

This platform consists of various systems. Therefore, providing a good user authentication system and usability are challenges. A unified user authentication system will be prepared so that each quantum computer and supercomputer can be used from any system. Additionally, by coordinating the job schedulers of each system, computational jobs can be submitted from any location. The design will aim to minimize waste from the perspective of efficient use of computing resources while maintaining user convenience.

Through the OpenOnDemand environment, users will be able to easily access the computing resources of quantum computers and supercomputers via a web browser. Additionally, various Python frameworks can be used within JupyterNotebook. Quantum software environments such as Qiskit, Qibo, and TKET will also be prepared using Singularity containers, allowing users to start developing quantum applications immediately.

Quantum computer simulations are also necessary. In this project, a new supercomputer system with GPUs will be installed for quantum simulations. We will also prepare the environment to run various quantum simulation software on this supercomputer.

While quantum computers are becoming practical, they are still in the development stage. There are many challenges in both hardware and software fields. Some issues would arise from the large-scale connection of various systems, such as a superconducting quantum computer, an ion trap quantum computer, and supercomputers with different architectures. This project prioritizes the installation and stable operation of the Quantum-HPC Hybrid platform infrastructure while aiming to maximize the efficient use of computing resources and user convenience. By advancing such complex and extensive platform construction, we can accumulate new knowledge, which can be utilized in future system construction.

What can be achieved by connecting quantum computers and supercomputers is still unknown. Many quantum researchers, HPC researchers, and application developers are interested in this new field. For these users, we will develop a Quantum-HPC Hybrid platform that is easily accessible anytime, anywhere.