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arXiv · 1109.3059

Filter-design perspective applying to dynamical decoupling of a multi-qubit system

Su Zhi-Kun·Jiang Shao-Ji
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Abstract

We employ the filter-design perspective and derive the filter functions according to nested Uhrig dynamical decoupling (NUDD) and Symmetric dynamical decoupling (SDD) in the pure-dephasing spin-boson model with N qubits. The performances of NUDD and SDD are discussed in detail for a two-qubit system. The analysis shows that (i) SDD outperforms NUDD for the bath with a soft cutoff while NUDD approaches SDD as the cutoff becomes harder; (ii) if the qubits are coupled to a common reservoir, SDD helps to protect the decoherence-free subspace while NUDD destroys it; (iii) when the the imperfect control pulses with finite width are considered, NUDD is affected in both the high-fidelity regime and coherence time regime while SDD is affected in the coherence time regime only.

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Su Zhi-Kun, Jiang Shao-Ji. 2011-11-28. Filter-design perspective applying to dynamical decoupling of a multi-qubit system. https://arxiv.org/abs/1109.3059

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