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arXiv · 2001.10257

Non-Bloch band collapse and chiral Zener tunneling

Stefano Longhi
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Abstract

Non-Bloch band theory describes bulk energy spectra and topological invariants in non-Hermitian crystals with open boundaries, where the bulk eigenstates are squeezed toward the edges (skin effect). However, the interplay of non-Bloch band theory, skin effect and coherent Bloch dynamics is so far unexplored. In two-band non-Hermitian lattices, it is shown here that collapse of non-Bloch bands and skin modes deeply changes the Bloch dynamics under an external force. In particular, for resonance forcing non-Bloch band collapse results in Wannier-Stark ladder coalescence and chiral Zener tunneling between the two dispersive Bloch bands.

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Stefano Longhi. 2020-01-28. Non-Bloch band collapse and chiral Zener tunneling. https://doi.org/10.1103/physrevlett.124.066602

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