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arXiv · 1209.0557

Quantum Error Correction with Uniformly Mixed State Ancillae

Yasushi Kondo·Chiara Bagnasco·Mikio Nakahara
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Abstract

It is often assumed that the ancilla qubits required for encoding a qubit in quantum error correction (QEC) have to be in pure states, $|00...0>$ for example. In this letter, we seek an encoding scheme, in which the ancillae may be in a uniformly mixed state. We demonstrate our scheme experimentally by making use of a three-qubit NMR quantum computer. Moreover, the encoded state has an interesting nature in terms of Quantum Discord, or purely quantum correlations between the data-qubit and ancillae.

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Yasushi Kondo, Chiara Bagnasco, Mikio Nakahara. 2012-10-04. Quantum Error Correction with Uniformly Mixed State Ancillae. https://doi.org/10.1103/physreva.88.022314

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