Analysis and minimization of bending losses in discrete quantum networks

  title={Analysis and minimization of bending losses in discrete quantum networks},
  author={Georgios M. Nikolopoulos and Anton{\'i}n Hoskovec and Igor Jex},
  journal={Physical Review A},
We study theoretically the transfer of quantum information along bends in two-dimensional discrete lattices. Our analysis shows that the fidelity of the transfer decreases considerably, as a result of interactions in the neighbourhood of the bend. It is also demonstrated that such losses can be controlled efficiently by the inclusion of a defect. The present results are of relevance to various physical implementations of quantum networks, where geometric imperfections with finite spatial extent… 

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Ωmax represents the upper limit on the achievable couplings within a physical realization of the chains, and is determined by physical or technological constraints

    This is a universal ratio for a given chain i.e., it does not depend on the actual position of the bend. If necessary


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      The effect ofV (θ) can be treated perturbatively only for κ ≪ 1. Moreover, for the protocols under consideration and the entire regime of parameters

        Detunings for κ 0.7 have to be taken with a pinch of salt, since they far exceed Ωmax and thus may not be realizable within certain physical platforms

          Stresses that remain after their original source (e.g., external forces, heat gradient) has been removed