The Error-corrected Universal Reconfigurable Ion-trap Quantum Archetype (EURIQA) project will create a quantum computer system at the logical qubit level. EURIQA is designed using individual trapped atomic ions in sufficient number to create a set of logical qubits to be used for reliable quantum computations based on a universal set of logic gates. Trapped ions are the only physical qubit that have been shown to have reached a minimum fidelity of at least 99.9% for state preparation and measurement [1-2], one- [3-5], and two-qubit gates [6].
A number of challenges still remain in creating a trapped ion quantum computer having sufficient fidelity when computing with many qubits. Namely, performing gates and ion state measurements with high fidelity while maintaining coherence on other adjacent qubits, applying a reliable error correction scheme, and effectively using classical controllers to implement complex and time-critical quantum operations.
With the EURIQA project, we address these issues from a system design perspective. To improve gate fidelities, the team will design a compact laser system and a compact ion trap system to shorten the optical distance. Shortening the laser propagation length will improve the quality of optical manipulations on the ions, improving the fidelity of those operations. The EURIQA team also endeavors to design and experimentally verify a method for optically addressing more than 30 qubits simultaneously. Access to larger numbers of physical qubits provides the possibility of an error correcting scheme to create logical qubits. Such a system will require new, expanded classical control capabilities.
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