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Bloch-Landau-Zener dynamics induced by a synthetic field in a photonic quantum walk

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 نشر من قبل Filippo Cardano
 تاريخ النشر 2020
  مجال البحث فيزياء
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Quantum walks are processes that model dynamics in coherent systems. Their experimental implementations proved key to unveil novel phenomena in Floquet topological insulators. Here we realize a photonic quantum walk in the presence of a synthetic gauge field, which mimics the action of an electric field on a charged particle. By tuning the energy gaps between the two quasi-energy bands, we investigate intriguing system dynamics characterized by the interplay between Bloch oscillations and Landau-Zener transitions. When both gaps at quasi-energy values 0 and $pi$ are vanishingly small, the Floquet dynamics follows a ballistic spreading.



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