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Entanglement purification for Quantum Computation

W. Dür·H. -J. Briegel
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Abstract

We show that thresholds for fault-tolerant quantum computation are solely determined by the quality of single-system operations if one allows for d-dimensional systems with $8 \leq d \leq 32$. Each system serves to store one logical qubit and additional auxiliary dimensions are used to create and purify entanglement between systems. Physical, possibly probabilistic two-system operations with error rates up to 2/3 are still tolerable to realize deterministic high quality two-qubit gates on the logical qubits. The achievable error rate is of the same order of magnitude as of the single-system operations. We investigate possible implementations of our scheme for several physical set-ups.

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W. Dür, H. -J. Briegel. 2003-02-17. Entanglement purification for Quantum Computation. https://doi.org/10.1103/physrevlett.90.067901

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