Optimal multiqubit operations for Josephson charge qubits.

Phys Rev Lett

Materials Physics Laboratory, Helsinki University of Technology, POB 2200 (Technical Physics), FIN-02015 HUT, Espoo, Finland.

Published: May 2003

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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http://dx.doi.org/10.1103/PhysRevLett.90.197901DOI Listing

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