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arXiv · 1101.3194

Chaos can act as a decoherence suppressor

Jing Zhang·Yu-xi Liu·Wei-Min Zhang·Lian-Ao Wu·Re-Bing Wu·Tzyh-Jong Tarn
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Abstract

We propose a strategy to suppress decoherence of a solid-state qubit coupled to non-Markovian noises by attaching the qubit to a chaotic setup with the broad power distribution in particular in the high-frequency domain. Different from the existing decoherence control methods such as the usual dynamics decoupling control, high-frequency components of our control are generated by the chaotic setup driven by a low-frequency field, and the generation of complex optimized control pulses is not necessary. We apply the scheme to superconducting quantum circuits and find that various noises in a wide frequency domain, including low-frequency $1/f$, high-frequency Ohmic, sub-Ohmic, and super-Ohmic noises, can be efficiently suppressed by coupling the qubits to a Duffing oscillator as the chaotic setup. Significantly, the decoherence time of the qubit is prolonged approximately $100$ times in magnitude.

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Jing Zhang, Yu-xi Liu, Wei-Min Zhang, Lian-Ao Wu, Re-Bing Wu, Tzyh-Jong Tarn. 2011-01-17. Chaos can act as a decoherence suppressor. https://doi.org/10.1103/physrevb.84.214304

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