High-Fidelity Adaptive Qubit Detection through Repetitive Quantum Nondemolition Measurements

Journal Article · Fri Sep 21 00:00:00 EDT 2007 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.99.120502· OSTI ID:21024165

Hume, D B; Rosenband, T; Wineland, D J ^[1]

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1. Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

Using two trapped ion species ({sup 27}Al{sup +} and {sup 9}Be{sup +}) as primary and ancillary quantum systems, we implement qubit measurements based on the repetitive transfer of information and quantum nondemolition detection. The repetition provides a natural mechanism for an adaptive measurement strategy, which leads to exponentially lower error rates compared to using a fixed number of detection cycles. For a single qubit we demonstrate 99.94% measurement fidelity. We also demonstrate a technique for adaptively measuring multiple qubit states using a single ancilla, and apply the technique to spectroscopy of an optical clock transition.

• OSTI ID: 21024165
• Journal Information: Physical Review Letters, Vol. 99, Issue 12; Other Information: DOI: 10.1103/PhysRevLett.99.120502; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALUMINIUM 27 BEAMS
BERYLLIUM 9 BEAMS
INFORMATION THEORY
QUANTUM MECHANICS
QUBITS
SPECTROSCOPY
TRAPPING