A fractal geometry immersed in a hierarchical magnetic flux distribution

Biplab Pal

doi:10.1063/5.0257273

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arXiv · 2406.12972

A fractal geometry immersed in a hierarchical magnetic flux distribution

Biplab Pal

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Abstract

Fractal geometry presents us with a self-similarity in their pattern at various length scales that is prevalent in our natural world. We present theoretical model of a Sierpinski gasket (SPG) fractal geometry with a deterministic perturbation in the form of a hierarchical distribution of magnetic flux. Such flux configuration induces a deterministic disorder in the Aharonov-Bohm (AB) phases picked up by the electron wavefunction. Using the tight-binding formalism, we show that by tunning the strength of the hierarchy parameter of those AB phases, one can systematically engineer quantum states in a SPG fractal lattice. In addition to this, we have also observed that by controlling the strength of this hierarchy parameter in the magnetic flux, one can effectively regulate the persistent current in the SPG fractal structure. This characteristic is found to be true for various filling factors. Our results could be useful for designing nanoelectronic devices using molecular fractal structures fabricated by chemical synthesis technique.

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cond-mat.mes-hall cond-mat.dis-nn cond-mat.stat-mech

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Biplab Pal. 2024-06-18. A fractal geometry immersed in a hierarchical magnetic flux distribution. https://doi.org/10.1063/5.0257273

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