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Multi-particle interferometry in the time-energy domain with localized topological quasiparticles

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 نشر من قبل Alex Zazunov
 تاريخ النشر 2019
  مجال البحث فيزياء
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We propose multi-particle interference protocols in the time-energy domain which are able to probe localized topological quasiparticles. Using a set of quantum dots tunnel-coupled to a topologically nontrivial system, the time dependence of the dot level energies defines a many-body interferometry platform which (to some extent) is similar to the Hong-Ou-Mandel (HOM) interferometer. We demonstrate that for a superconducting island harboring at least four Majorana bound states, the probability distribution of the final dot occupation numbers will exhibit a characteristic interferometric pattern with robust and quantized $pi$ phase shifts. This pattern is shown to be qualitatively different for topologically trivial variants of our setup. Apart from identifying the presence of topological quasiparticles, the interferometer can be used to manipulate the quantum state in the topologically nontrivial sector by means of post-selection.



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