Absolutely continuous energy bands in the electronic spectrum of quasiperiodic ladder networks

Biplab Pal; Arunava Chakrabarti

doi:10.1016/j.physe.2014.02.022

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arXiv · 1310.3372

Absolutely continuous energy bands in the electronic spectrum of quasiperiodic ladder networks

Biplab Pal·Arunava Chakrabarti

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Abstract

The energy spectra of quasi-one dimensional quasiperiodic ladder networks are analyzed within a tight binding description. In particular, we show that if a selected set of sites in each strand of a ladder is tunnel-coupled to quantum dots attached from a side, absolutely continuous subbands can be generated in the spectrum if one tunes the dot potential and the dot-strand coupling appropriately. Typical cases with two and three strand Fibonacci ladders in the off diagonal model are discussed in details. We also discuss the possibility of re-entrant insulator-metal transition for a general n-strand ladder network when n becomes large. The observations remain valid even in the case of a disordered ladder network with the same constituents. The results are analytically exact.

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BibTeX RIS

Biplab Pal, Arunava Chakrabarti. 2014-01-14. Absolutely continuous energy bands in the electronic spectrum of quasiperiodic ladder networks. https://doi.org/10.1016/j.physe.2014.02.022

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