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Generalized Aubry-Andre self-duality and Mobility edges in non-Hermitian quasi-periodic lattices

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 نشر من قبل Tong Liu
 تاريخ النشر 2020
  مجال البحث فيزياء
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We demonstrate the existence of generalized Aubry-Andre self-duality in a class of non-Hermitian quasi-periodic lattices with complex potentials. From the self-duality relations, the analytical expression of mobility edges is derived. Compared to Hermitian systems, mobility edges in non-Hermitian ones not only separate localized from extended states, but also indicate the coexistence of complex and real eigenenergies, making it possible a topological characterization of mobility edges. An experimental scheme, based on optical pulse propagation in synthetic photonic mesh lattices, is suggested to implement a non-Hermitian quasi-crystal displaying mobility edges.

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