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arXiv · 1708.02634

Generation of high-fidelity quantum control methods for multi-level systems

J. Randall·A. M. Lawrence·S. C. Webster·S. Weidt·N. V. Vitanov·W. K. Hensinger
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Abstract

In recent decades there has been a rapid development of methods to experimentally control individual quantum systems. A broad range of quantum control methods has been developed for two-level systems, however the complexity of multi-level quantum systems make the development of analogous control methods extremely challenging. Here, we exploit the equivalence between multi-level systems with SU(2) symmetry and spin-1/2 systems to develop a technique for generating new robust, high-fidelity, multi-level control methods. As a demonstration of this technique, we develop new adiabatic and composite multi-level quantum control methods and experimentally realise these methods using an $^{171}$Yb$^+$ ion system. We measure the average infidelity of the process in both cases to be around $10^{-4}$, demonstrating that this technique can be used to develop high-fidelity multi-level quantum control methods and can, for example, be applied to a wide range of quantum computing protocols including implementations below the fault-tolerant threshold in trapped ions.

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J. Randall, A. M. Lawrence, S. C. Webster, S. Weidt, N. V. Vitanov, W. K. Hensinger. 2018-09-13. Generation of high-fidelity quantum control methods for multi-level systems. https://doi.org/10.1103/physreva.98.043414

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