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

作者：Pal Biplab; Chakrabarti Arunava^*

来源：Physica E: Low-Dimensional Systems and Nanostructures , 2014, 60: 188-195.

DOI：10.1016/j.physe.2014.02.022

• Aperiodic nanostructure
• Metal-insulator transition
• Charge transport

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.

• 出版日期2014-6