The Loss of fidelity due to quantum leakage for Josephson charge qubits
نویسندگان
چکیده
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 EJ/Ech ∼ 0.02, the loss of the fidelity per elementary operation is about 10 which satisfy the DiVincenzo’s low decoherence criterion. By appropriately improving the design of the Josephson junction, namely, decreasing EJ/Ech to ∼ 0.01, the loss of fidelity per elementary operation can decrease to 10 even smaller. PACS numbers: 03.67. Lx, 73.23.-b
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