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arXiv · 1309.0198

Reducing intrinsic decoherence in a superconducting circuit by quantum error detection

Y. P. Zhong·Z. L. Wang·John M. Martinis·A. N. Cleland·A. N. Korotkov·H. Wang
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Abstract

A fundamental challenge for quantum information processing is reducing the impact of environmentally-induced errors. Quantum error detection (QED) provides one approach to handling such errors, in which errors are rejected when they are detected. Here we demonstrate a QED protocol based on the idea of quantum un-collapsing, using this protocol to suppress energy relaxation due to the environment in a three-qubit superconducting circuit. We encode quantum information in a target qubit, and use the other two qubits to detect and reject errors caused by energy relaxation. This protocol improves the storage time of a quantum state by a factor of roughly three, at the cost of a reduced probability of success. This constitutes the first experimental demonstration of an algorithm-based improvement in the lifetime of a quantum state stored in a qubit.

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Y. P. Zhong, Z. L. Wang, John M. Martinis, A. N. Cleland, A. N. Korotkov, H. Wang. 2013-09-01. Reducing intrinsic decoherence in a superconducting circuit by quantum error detection. https://doi.org/10.1038/ncomms4135

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