Project for the development of a diamond-based quantum processor

Setup for the simulation of chemical processes in the quantum computing project QC4BW

Press release by HQS Quantum Simulation /

HQS Quantum Simulations provides setups for simulating chemical systems such as metal-organic frameworks (MOFs) on quantum computers on behalf of Fraunhofer IAF and ICT. The QC4BW project is developing a diamond-based quantum processor. Its performance will be evaluated using quantum chemical calculations.

Logo of the project QC4BW coordinated by Fraunhofer IAF
© Fraunhofer IAF
In the QC4BW project, researchers coordinated by Fraunhofer IAF are developing a diamond-based quantum processor.

The joint project QC4BW focuses on the development of a diamond-based quantum processor based on the unique properties of diamond color centers. The project started in January 2021 and the second phase of the project, which was initiated at the beginning of the year, will be completed in March 2024.

To store and process quantum information, the diamond colour centers use the spins of electrons and atomic nuclei as quantum bits (qubits). The diamond-based quantum processor is based on a new generation of spin-based quantum registers and has integrated memory functions for quantum mechanical states. To assess its suitability for application-relevant quantum computing tasks, the unique performance of the diamond-based quantum processor will be analyzed in comparison with superconducting qubit technologies. IBM’s Quantum System One quantum computer will be available for these calculations.

The storage of CO2 in metal-organic framework compounds and electronic excitations in organic molecules are being investigated as chemical applications. On behalf of Fraunhofer IAF and ICT, HQS has provided a setup tailored to such chemical systems to perform parts of the simulations on a quantum processor. HQS realized this with the help of its open-source application, the Active Space Finder (ASF), which automates the selection of active orbitals in molecules: The selection process determines the most important orbitals to be mapped on the quantum computer.

As part of the work, HQS has determined specific active spaces of different sizes for the various molecular systems. At the same time, the numbers of active orbitals are optimal to be mapped either on a diamond-based quantum processor currently under development, or on other systems such as the IBM Quantum System One. The software supplied implements the complete workflow from the molecular structure to the calculation of energetic quantities using the quantum chemistry software PySCF. An interface to the Qiskit software is used to integrate the quantum computer.

The aim is to advance the application of quantum technology in areas such as molecular modeling and chemical research. New insights into molecular modeling can be gained through simulations on the diamond-based quantum processor.

About QC4BW

The joint project QC4BW with the working title “Development and benchmarking of a diamond-based, spintronic quantum register for a scalable quantum processor” is a joint project under the leadership of the Fraunhofer Institute for Applied Solid State Physics IAF. The partners involved include the Fraunhofer Institute for Chemical Technology ICT, the Karlsruhe Institute of Technology (KIT), the University of Stuttgart, the University of Ulm, and the University of Constance. This pioneering project is part of the Baden-Württemberg Competence Center for Quantum Computing (KQCBW) and is funded by the Baden-Württemberg Ministry of Economic Affairs, Labour, and Tourism.

About HQS Quantum Simulations

HQS Quantum Simulations was founded in 2017 as a Karlsruhe Institute of Technology (KIT) spin-off and develops software to simulate quantum systems. The start-up’s software works on regular computers but can be easily transferred to quantum computers. HQS Quantum Simulations intends this approach to allow companies and researchers to transition their simulation workflow quickly and efficiently to quantum computing as soon as it becomes available.


The use of the photo is permitted exclusively in connection with this press release and with indication of the copyright.

Logo of the Ministry of Economy, Labor and Tourism Baden-Württemberg


The QC4BW project is funded by the Baden-Württemberg Ministry of Economic Affairs, Labour and Tourism as part of the Competence Center Quantum Computing Baden-Württemberg.

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