Robust optimal quantum gates for Josephson charge qubits

Abstract

Quantum optimal control theory allows to design accurate quantum gates. We employ it to design high-fidelity two-bit gates for Josephson charge qubits in the presence of both leakage and noise. Our protocol considerably increases the fidelity of the gate and, more important, it is quite robust in the disruptive presence of 1/f noise. The improvement in the gate performances discussed in this work (errors of the order of 10^{-3}-10^{-4} in realistic cases) allows to cross the fault tolerance threshold.

4 pages, 4 figures

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Cited by in corpus (6)

• Fault-Tolerant Computing With Biased-Noise Superconducting Qubits
• Optimal control of entangling operations for trapped ion quantum computing
• Optimal control of a leaking qubit
• Photon storage in Lambda-type optically dense atomic media. IV. Optimal control using gradient ascent
• Optimal control of atom transport for quantum gates in optical lattices
• Time-optimal performance of Josephson charge qubits: A process tomography approach