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Persistent currents with long-range hopping in 1D single-isolated-diffusive rings

Santanu K. Maiti·J. Chowdhury·S. N. Karmakar
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Abstract

We show from exact calculations that a simple tight-binding Hamiltonian with diagonal disorder and long-range hopping integrals, falling off as a power $μ$ of the inter-site separation, correctly describes the experimentally observed amplitude (close to the value of an ordered ring) and flux-periodicity ($hc/e$) of persistent currents in single-isolated-diffusive normal metal rings of mesoscopic size. Long-range hopping integrals tend to delocalize the electrons even in the presence of disorder resulting orders of magnitude enhancement of persistent current relative to earliar predictions.

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Santanu K. Maiti, J. Chowdhury, S. N. Karmakar. 2006-02-05. Persistent currents with long-range hopping in 1D single-isolated-diffusive rings. https://doi.org/10.1016/j.synthmet.2005.09.030

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