Two-qubit gate operations in superconducting circuits with strong coupling and weak anharmonicity
نویسندگان
چکیده
We theoretically study the implementation of two-qubit gates in a system of two coupled superconducting qubits. In particular, we analyze two-qubit gate operations under the condition that the coupling strength is comparable with or even larger than the anharmonicity of the qubits. By numerically solving the time-dependent Schrödinger equation under the assumption of negligible decoherence, we obtain the dependence of the twoqubit gate fidelity on the system parameters in the case of both direct and indirect qubit–qubit coupling. Our numerical results can be used to identify the ‘safe’ parameter regime for experimentally implementing two-qubit gates with high fidelity in these systems. 5 Author to whom any correspondence should be addressed. New Journal of Physics 14 (2012) 073041 1367-2630/12/073041+13$33.00 © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft
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