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A two reservoir model of quantum error correction

James P. Clemens·Julio Gea-Banacloche
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Abstract

We consider a two reservoir model of quantum error correction with a hot bath causing errors in the qubits and a cold bath cooling the ancilla qubits to a fiducial state. We consider error correction protocols both with and without measurement of the ancilla state. The error correction acts as a kind of refrigeration process to maintain the data qubits in a low entropy state by periodically moving the entropy to the ancilla qubits and then to the cold reservoir. We quantify the performance of the error correction as a function of the reservoir temperatures and cooling rate by means of the fidelity and the residual entropy of the data qubits. We also make a comparison with the continuous quantum error correction model of Sarovar and Milburn [Phys. Rev. A 72 012306].

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James P. Clemens, Julio Gea-Banacloche. 2005-08-22. A two reservoir model of quantum error correction. https://doi.org/10.1103/physreva.73.022337

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