We are developing a qualification system to analyse the functionality and properties of solid-state spin qubits.
Quantum computers can be built using a variety of physical systems, including flaws in the crystal lattice of solids, where a defect becomes a useful qubit. However, these defects must be created with certain properties, in a reproducible manner that ensures high quality in order to later be used to execute quantum algorithms without errors. With our qualification system, we enable feedback at an early stage of the fabrication process and the design of the initialisation concepts, and thus assist with the production of higher-quality spin qubits.
One of the problems to be solved in order to realise a practical quantum computer is to ensure the consistent quality of the qubits. In order for a solution to be scalable, it is not only the qubits themselves that must be reproducible in high quality, but also the initialisation and control of the overall system. This is particularly true for qubits based on defects in solids, whose fabrication represents a fundamental step towards their practical use.
Automated and scalable quality analysis is essential for improving the underlying expansion and production processes. Similarly, a test platform is needed for the evaluation of scalability and fault tolerance that makes the various initialisation techniques and scenarios accessible and thus enables the iterative optimisation of quantum hardware.Challenge
The rapid progress in the development of quantum computers means that a system designed to assess qubit technologies must be highly flexible. Such a system must be able to test as many scenarios and variables as possible in order to enable the analysis of new progress and to streamline the feedback loop for development and innovation.
Flexibility, especially in the detection and control of solid-state spin qubits, is a major challenge here, since there is a large ‘zoo’ of possible different defects. This extends over very large ranges in terms of optical wavelengths, operating temperatures and the radio frequency spectrum used for spin control. We are developing suitable solutions for these problems together with our partners within the DLR Quantum Computing Initiative.