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arXiv · 1806.02413

Achieving High-Fidelity Single-Qubit Gates in a Strongly Driven Charge Qubit with $1\!/\!f$ Charge Noise

Yuan-Chi Yang·S. N. Coppersmith·Mark Friesen
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Abstract

Charge qubits formed in double quantum dots represent quintessential two-level systems that enjoy both ease of control and efficient readout. Unfortunately, charge noise can cause rapid decoherence, with typical single-qubit gate fidelities falling below $90\%$. Here, we develop analytical methods to study the evolution of strongly driven charge qubits, for general and $1\!/\!f$ charge-noise spectra. We show that special pulsing techniques can simultaneously suppress errors due to strong driving and charge noise, yielding single-qubit gates with fidelities above $99.9\%$. These results demonstrate that quantum dot charge qubits provide a potential route to high-fidelity quantum computation.

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Yuan-Chi Yang, S. N. Coppersmith, Mark Friesen. 2018-06-06. Achieving High-Fidelity Single-Qubit Gates in a Strongly Driven Charge Qubit with $1\!/\!f$ Charge Noise. https://doi.org/10.1038/s41534-019-0127-1

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