Superconductivity in correlated carbon nanotubes under pressure: A Bogoliubov-de Gennes study

Germán E. López; Chumin Wang

doi:10.1016/j.physb.2023.415602

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arXiv · 2312.06011

Superconductivity in correlated carbon nanotubes under pressure: A Bogoliubov-de Gennes study

Germán E. López·Chumin Wang

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Abstract

In contrast to most microscopic theories of superconductivity based on the reciprocal space, the Bogoliubov-de Gennes (BdG) formalism provides a real-space alternative for addressing inhomogeneous systems. In this article, we study the superconducting states in correlated single-walled carbon nanotubes (SWNTs) with curvature and spin-orbit corrections, as well as the inter-tube interaction through a connecting molecule using an attractive Hubbard model. The results reveal a close relationship between the on-site superconducting gap and the single-electron local density of states. For the limiting case of independent large-diameter nanotubes, the BdG equations can be reduced to the standard Bardeen-Cooper-Schrieffer one with analytical solutions. Moreover, an optimal separation between nanotubes is found, which leads to a maximal superconducting critical temperature. This finding has a remarkable accordance with the experimental data obtained from Buckypapers built of boron doped SWNTs under external pressure.

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Germán E. López, Chumin Wang. 2023-12-10. Superconductivity in correlated carbon nanotubes under pressure: A Bogoliubov-de Gennes study. https://doi.org/10.1016/j.physb.2023.415602

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