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arXiv · 1812.00454

Hamiltonian quantum computing with superconducting qubits

Alessandro Ciani·Barbara M. Terhal·David P. DiVincenzo
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Abstract

We consider how the Hamiltonian Quantum Computing scheme introduced in [arXiv:1509.01278] can be implemented using a 2D array of superconducting transmon qubits. We show how the scheme requires the engineering of strong attractive cross-Kerr and weak flip-flop or hopping interactions and we detail how this can be achieved. Our proposal uses a new electric circuit for obtaining the attractive cross-Kerr coupling between transmons via a dipole-like element. We discuss and numerically analyze the forward motion and execution of the computation and its dependence on coupling strengths and their variability. We extend [arXiv:1509.01278] by explicitly showing how to construct a direct Toffoli gate, thus establishing computational universality via the Hadamard and Toffoli gate or via controlled-Hadamard, Hadamard and CNOT.

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Alessandro Ciani, Barbara M. Terhal, David P. DiVincenzo. 2018-12-02. Hamiltonian quantum computing with superconducting qubits. https://doi.org/10.1088/2058-9565%2Fab18dd

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