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arXiv · 2401.05147

Strictly one dimensional behavior emerging from dispersive two dimensional system: implications on metallic nanowires on semiconducting substrates

Abstract

We studied single and two Su-Shreiffer-Heeger wires on a simple cubic semiconducting substrate. The wire-wire coupling is either perpendicular or diagonal hopping respecting the particle-hole and time-reversal symmetries. The hybridization to the substrate renormalizes the model parameters of the wires towards the hopping parameter of the substrate without changing the basic nature of perpendicular or diagonal coupling and it can mediate effective perpendicular hopping but not diagonal hopping in the absence of direct wire-wire coupling. This justifies the investigation of multi uniform tight binding wires with perpendicular or diagonal hopping parameters while neglecting the substrate. Perpendicularly coupled uniform wires reveal an anisotropic two dimensional band dispersion. Diagonally coupled uniform wires reveal strictly one dimensional bands parallel to the wires direction if the intra-wire hopping parameter is larger than twice the diagonal hopping parameter despite strong dispersion perpendicular to the wires. Otherwise, they reveal strictly one dimensional bands parallel and perpendicular to the wires direction simultaneously. We established the possibility of realizing strictly one dimensional properties emerging from dispersive two dimensional systems if time-reversal and particle-hole symmetries are respected. This can facilitate the investigations of Luttinger liquid in the Au/Ge(001) and Bi/InSb(001) surface reconstructions.

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Keshab Sony, Anas Abdelwahab. 2024-04-01. Strictly one dimensional behavior emerging from dispersive two dimensional system: implications on metallic nanowires on semiconducting substrates. https://doi.org/10.1103/physrevb.109.165431

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