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arXiv · 1409.3624

Wannier-Stark states in double-periodic lattices I: one-dimensional lattices

D. N. Maksimov·E. N. Bulgakov·A. R. Kolovsky
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Abstract

We analyze the Wannier-Stark spectrum of a quantum particle in generic one-dimensional double-periodic lattices. In the limit of weak static field the spectrum is shown to be a superposition of two Wannier-Stark ladders originated from two Bloch subbands. As the strength of the field is increased, the spectrum rearranges itself into a single Wannier-Stark ladder. We derive analytical expressions which describe the rearrangement employing the analogy between the Wannier-Stark problem and the driven two-level system in the strong-coupling regime.

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D. N. Maksimov, E. N. Bulgakov, A. R. Kolovsky. 2014-11-24. Wannier-Stark states in double-periodic lattices I: one-dimensional lattices. https://doi.org/10.1103/physreva.91.053631

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