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arXiv · 1911.06272

Long-lived coherence in driven spin systems: from two to infinite spatial dimensions

Walter Hahn·V. V. Dobrovitski
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Abstract

Long-lived coherences, emerging under periodic pulse driving in the disordered ensembles of strongly interacting spins, offer immense advantages for future quantum technologies, but the physical origin and the key properties of this phenomenon remain poorly understood. We theoretically investigate this effect in ensembles of different dimensionality, and predict existence of the long-lived coherences in two-dimensional and infinite-dimensional (where every spin is coupled to all others) systems, which are of particular importance for quantum sensing and quantum information processing. We explore the transition from two to infinite dimensions, and show that the long-time coherence dynamics in all dimensionalities is qualitatively similar, although the short-time behavior is drastically different, exhibiting dimensionality-dependent singularity. Our study establishes the common physical origin of the long-lived coherences in different dimensionalities, and suggests that this effect is a generic feature of the strongly coupled spin systems with positional disorder. Our results lay out foundation for utilizing the long-lived coherences in a range of application, from quantum sensing with two-dimensional spin ensembles, to quantum information processing with the infinitely-dimensional spin systems in the cavity-QED settings.

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Walter Hahn, V. V. Dobrovitski. 2021-07-12. Long-lived coherence in driven spin systems: from two to infinite spatial dimensions. https://doi.org/10.1088/1367-2630%2Fac1000

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