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arXiv · 0704.1464

Distributed quantum information processing with minimal local resources

Earl T. Campbell
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Abstract

We present a protocol for growing graph states, the resource for one-way quantum computing, when the available entanglement mechanism is highly imperfect. The distillation protocol is frugal in its use of ancilla qubits, requiring only a single ancilla qubit when the noise is dominated by one Pauli error, and two for a general noise model. The protocol works with such scarce local resources by never post-selecting on the measurement outcomes of purification rounds. We find that such a strategy causes fidelity to follow a biased random walk, and that a target fidelity is likely to be reached more rapidly than for a comparable post-selecting protocol. An analysis is presented of how imperfect local operations limit the attainable fidelity. For example, a single Pauli error rate of 20% can be distilled down to $\sim 10$ times the imperfection in local operations.

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Earl T. Campbell. 2007-10-09. Distributed quantum information processing with minimal local resources. https://doi.org/10.1103/physreva.76.040302

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