Ancilla-driven universal quantum computation

Journal Article · Sun Aug 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.020301· OSTI ID:21448409

Anders, Janet; Browne, Dan E ^[1]; Oi, Daniel K. L. ^[2]; Kashefi, Elham ^[3]; Andersson, Erika ^[4]

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1. Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)
2. SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)
3. School of Informatics, University of Edinburgh, Edinburgh EH8 9AB (United Kingdom)
4. SUPA, Department of Physics, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

We introduce a model of quantum computation intermediate between the gate-based and measurement-based models. A quantum register is manipulated remotely with the help of a single ancilla that ''drives'' the evolution of the register. The fully controlled ancilla qubit is coupled to the computational register only via a fixed unitary two-qubit interaction and then measured in suitable bases, driving both single- and two-qubit operations on the register. Arbitrary single-qubit operations directly on register qubits are not needed. We characterize all interactions E that induce a unitary, stepwise deterministic measurement back-action on the register sufficient to implement any quantum channel. Our scheme offers experimental advantages for computation, state preparation, and generalized measurements, since no tunable control of the register is required.

• OSTI ID: 21448409
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CALCULATION METHODS
COMPUTERS
CONTROL
INFORMATION
MECHANICS
QUANTUM COMPUTERS
QUANTUM INFORMATION
QUANTUM MECHANICS
QUANTUM STATES
QUBITS