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arXiv · 1810.07117

Universal Uhrig dynamical decoupling for bosonic systems

Margret Heinze·Robert Koenig
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Abstract

We construct efficient deterministic dynamical decoupling schemes protecting continuous variable degrees of freedom. Our schemes target decoherence induced by quadratic system-bath interactions with analytic time-dependence. We show how to suppress such interactions to $N$-th order using only $N$ pulses. Furthermore, we show to homogenize a $2^m$-mode bosonic system using only $(N+1)^{2m+1}$ pulses, yielding - up to $N$-th order - an effective evolution described by non-interacting harmonic oscillators with identical frequencies. The decoupled and homogenized system provides natural decoherence-free subspaces for encoding quantum information. Our schemes only require pulses which are tensor products of single-mode passive Gaussian unitaries and SWAP gates between pairs of modes.

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Margret Heinze, Robert Koenig. 2018-10-16. Universal Uhrig dynamical decoupling for bosonic systems. https://doi.org/10.1103/physrevlett.123.010501

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