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arXiv · 0801.2670

Metal-insulator transition in an aperiodic ladder network: an exact result

Shreekantha Sil·Santanu K. Maiti·Arunava Chakrabarti
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Abstract

We show, in a completely analytical way, that a tight binding ladder network composed of atomic sites with on-site potentials distributed according to the quasiperiodic Aubry model can exhibit a metal-insulator transition at multiple values of the Fermi energy. For specific values of the first and second neighbor electron hopping, the result is obtained exactly. With a more general model, we calculate the two-terminal conductance numerically. The numerical results corroborate the analytical findings and yield a richer variety of spectrum showing multiple mobility edges.

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Shreekantha Sil, Santanu K. Maiti, Arunava Chakrabarti. 2008-07-15. Metal-insulator transition in an aperiodic ladder network: an exact result. https://doi.org/10.1103/physrevlett.101.076803

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