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Quantum logic gates for coupled superconducting phase qubits

Frederick W. Strauch·Philip R. Johnson·Alex J. Dragt·C. J. Lobb·J. R. Anderson·F. C. Wellstood
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Abstract

Based on a quantum analysis of two capacitively coupled current-biased Josephson junctions, we propose two fundamental two-qubit quantum logic gates. Each of these gates, when supplemented by single-qubit operations, is sufficient for universal quantum computation. Numerical solutions of the time-dependent Schroedinger equation demonstrate that these operations can be performed with good fidelity.

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Frederick W. Strauch, Philip R. Johnson, Alex J. Dragt, C. J. Lobb, J. R. Anderson, F. C. Wellstood. 2003-10-21. Quantum logic gates for coupled superconducting phase qubits. https://doi.org/10.1103/physrevlett.91.167005

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