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Fast entanglement of two charge-phase qubits through nonadiabatic coupling to a large junction

Y. D. Wang·P. Zhang·D. L. Zhou·C. P. Sun
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Abstract

We propose a theoretical protocol for quantum logic gates between two Josephson junction charge-phase qubits through the control of their coupling to a large junction. In the low excitation limit of the large junction when $E_{J}\gg E_{c}$, it behaves effectively as a quantum data-bus mode of a harmonic oscillator. Our protocol is efficient and fast. In addition, it does not require the data-bus to stay adiabatically in its ground state, as such it can be implemented over a wide parameter regime independent of the data-bus quantum state.

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Y. D. Wang, P. Zhang, D. L. Zhou, C. P. Sun. 2004-01-06. Fast entanglement of two charge-phase qubits through nonadiabatic coupling to a large junction. https://doi.org/10.1103/physrevb.70.224515

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