Quantum information processing has reached an inflection point transitioning from proof of principle scientific experiments to small noisy quantum processors. To accelerate this process, it is necessary to provide the scientific community with access to testbed systems that provide full specifications, enable low-level access to native gate implementations, make vertical integration approaches possible, and provide ways to fully specify scheduling of gates. Access to noisy intermediate-scale quantum (NISQ) systems is needed to understand and optimize the noise properties, learn how to characterize and validate quantum operation, and to incubate the development and optimization of quantum algorithms for scientific applications.
The Quantum Scientific Computing Open User Testbed (QSCOUT) is a 5-year DOE program funded by the Office of Science’s Advanced Scientific Computing Research (ASCR) program to build a quantum testbed based on trapped ions that is available to the research community. As an open platform, it will not only provide full specifications and control for the realization of all high- level quantum and classical processes, it will also enable researchers to investigate, alter, and optimize the internals of the testbed and test more advanced implementations of quantum operations. QSCOUT will be made operational in stages, with each stage adding more ion qubits, greater classical control, and improved fidelities. We will leverage the specific strengths of trapped ion systems: the identical qubits with long qubit coherence times, the high-fidelity single and multi-qubit operations possible in these systems, the low cross-talk addressing of individual qubits in the register, and the all-to-all connectivity available in trapped ion quantum registers. In the first stage, we will make a quantum register of 3 qubits available. Parallel single qubit gates and sequential two-qubit Mølmer-Sørensen gates between any pair of qubits will be available. Target fidelities for single qubit operations are 99.5%, target fidelities for two-qubit gates are 98%. At the beginning of a computation, each quantum bit is prepared in the |0〉 state of the z-basis. At the end of a computation the entire quantum register is measured in the z-basis. For each measurement of the quantum register, the state of each qubit will be available to users.
The QSCOUT system will enable the understanding of noise properties of current quantum processors, it will teach us how to calibrate, characterize, and validate quantum processors. It will also help us to understand the limitations of current testbed systems and develop the next generation of larger more capable quantum processors featuring more quantum bits and higher fidelities. Furthermore, the availability of a real testbed system will nurture the development and optimization of quantum algorithms to solve scientific problems on quantum processors available in the future.
QSCOUT will also serve the greater quantum information sciences community by providing the possibility to develop the next generation of quantum computer scientists in academia, industry, and government.