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On the Harmonic approximation for large Josephson junction coupling charge qubits

T. Shi·B. Chen·Z. Song·C. P. Sun
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Abstract

We revisit the harmonic approximation (HA) for a large Josephson junction interacting with some charge qubits through the variational approach for the quantum dynamics of the junction-qubit coupling system. By making use of numerical calculation and analytical treatment, the conditions under which HA works well can be precisely presented to control the parameters implementing the two-qubit quantum logical gate through the couplings to the large junction with harmonic oscillator (HO) Hamiltonian.

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T. Shi, B. Chen, Z. Song, C. P. Sun. 2004-09-23. On the Harmonic approximation for large Josephson junction coupling charge qubits. https://doi.org/10.1088/0253-6102%2F43%2F5%2F006

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