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Optimal multiqubit operations for Josephson charge qubits

Antti O. Niskanen·Juha J. Vartiainen·Martti M. Salomaa
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Abstract

We introduce a method for finding the required control parameters for a quantum computer that yields the desired quantum algorithm without invoking elementary gates. We concentrate on the Josephson charge-qubit model, but the scenario is readily extended to other physical realizations. Our strategy is to numerically find any desired double- or triple-qubit gate. The motivation is the need to significantly accelerate quantum algorithms in order to fight decoherence.

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Antti O. Niskanen, Juha J. Vartiainen, Martti M. Salomaa. 2003-02-07. Optimal multiqubit operations for Josephson charge qubits. https://doi.org/10.1103/physrevlett.90.197901

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