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Coupling of Josephson current qubits using a connecting loop

Mun Dae Kim·Jongbae Hong
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Abstract

We propose a coupling scheme for the three-Josephson junction qubits which uses a connecting loop, but not mutual inductance. Present scheme offers the advantages of a large and tunable level splitting in implementing the controlled-NOT (CNOT) operation. We calculate the switching probabilities of the coupled qubits in the CNOT operations and demonstrate that present CNOT gate can meet the criteria for the fault-tolerant quantum computing. We obtain the coupling strength as a function of the coupling energy of the Josephson junction and the length of the connecting loop which varies with selecting two qubits from the scalable design.

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Mun Dae Kim, Jongbae Hong. 2004-09-24. Coupling of Josephson current qubits using a connecting loop. https://doi.org/10.1103/physrevb.70.184525

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