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arXiv · 0807.4058

Universality of Uhrig dynamical decoupling for suppressing qubit pure dephasing and relaxation

Wen Yang·Ren-Bao Liu
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Abstract

The optimal $N$-pulse dynamical decoupling discovered by Uhrig for a spin-boson mmodel [Phys. Rev. Lett, {\bf 98}, 100504 (2007)] is proved to be universal in suppressing to $O(T^{N+1})$ the pure dephasing or the longitudinal relaxation of a qubit (or spin-1/2) coupled to a generic bath in a short-time evolution of duration $T$. It is also found that for the purpose of suppressing the longitudinal relaxation, an ideal Uhrig $π$-pulse sequence can be generalized to a sequence consisting of the ideal one superimposed with finite-duration pulses satisfying certain symmetry requirements.

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Wen Yang, Ren-Bao Liu. 2008-07-25. Universality of Uhrig dynamical decoupling for suppressing qubit pure dephasing and relaxation. https://doi.org/10.1103/physrevlett.101.180403

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