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arXiv · 1206.6087

Long-time Low-latency Quantum Memory by Dynamical Decoupling

Kaveh Khodjasteh·Jarrah Sastrawan·David Hayes·Todd J. Green·Michael J. Biercuk·Lorenza Viola
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Abstract

Quantum memory is a central component for quantum information processing devices, and will be required to provide high-fidelity storage of arbitrary states, long storage times and small access latencies. Despite growing interest in applying physical-layer error-suppression strategies to boost fidelities, it has not previously been possible to meet such competing demands with a single approach. Here we use an experimentally validated theoretical framework to identify periodic repetition of a high-order dynamical decoupling sequence as a systematic strategy to meet these challenges. We provide analytic bounds-validated by numerical calculations-on the characteristics of the relevant control sequences and show that a "stroboscopic saturation" of coherence, or coherence plateau, can be engineered, even in the presence of experimental imperfection. This permits high-fidelity storage for times that can be exceptionally long, meaning that our device-independent results should prove instrumental in producing practically useful quantum technologies.

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Kaveh Khodjasteh, Jarrah Sastrawan, David Hayes, Todd J. Green, Michael J. Biercuk, Lorenza Viola. 2012-06-26. Long-time Low-latency Quantum Memory by Dynamical Decoupling. https://doi.org/10.1038/ncomms3045

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