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The Loss of fidelity due to quantum leakage for Josephson charge qubits

Xian-Ting Liang·Yong-Jian Xiong
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Abstract

In this paper we calculate the loss of fidelity due to quantum leakage for the Josephson charge qubit (JCQ) in virtue of the Mathieu functions. It is shown that for an present typical parameters of JCQ E_{J}/E_{ch}~0.02, the loss of the fidelity per elementary operation is about 10^(-4) which satisfy the DiVincenzo's low decoherence criterion. By appropriately improving the design of the Josephson junction, namely, decreasing E_{J}/E_{ch} to 0.01, the loss of fidelity per elementary operation can decrease to 10^(-6) even smaller.

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Xian-Ting Liang, Yong-Jian Xiong. 2004-07-05. The Loss of fidelity due to quantum leakage for Josephson charge qubits. https://doi.org/10.1142/s0217984905008268

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