Improving the performance of probabilistic programmable quantum processors

Journal Article · Thu Apr 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.042311· OSTI ID:20640957

Hillery, Mark ^[1]; Ziman, Mario ^[2]; Buzek, Vladimir ^[2]

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1. Department of Physics, Hunter College of CUNY, 695 Park Avenue, New York, New York 10021 (United States)
2. Research Center for Quantum Information, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia)

We present a systematic analysis of how one can improve performance of probabilistic programmable quantum processors. We generalize a simple Vidal-Masanes-Cirac processor that realizes U(1) rotations on a qubit with the phase of the rotation encoded in a state of the program register. We show how the probability of success of the probabilistic processor can be enhanced by using the processor in loops. In addition we show that the same strategy can be utilized for a probabilistic implementation of nonunitary transformations on qubits. In addition, we show that an arbitrary SU(2) transformation of qubits can be encoded in program state of a universal programmable probabilistic quantum processor. The probability of success of this processor can be enhanced by a systematic correction of errors via conditional loops. Finally, we show that all our results can be generalized also for qudits. In particular, we show how to implement SU(N) rotations of qudits via programmable quantum processor and how the performance of the processor can be enhanced when it is used in loops.

• OSTI ID: 20640957
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CORRECTIONS
ERRORS
IMPLEMENTATION
INFORMATION THEORY
PERFORMANCE
PROBABILISTIC ESTIMATION
PROBABILITY
QUANTUM MECHANICS
ROTATION
SU-2 GROUPS
TRANSFORMATIONS