Coherent transport in non-Abelian quantum graphs

A. V. Poshakinskiy; L. E. Golub

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arXiv · 2605.03826

Coherent transport in non-Abelian quantum graphs

A. V. Poshakinskiy·L. E. Golub

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Abstract

We study quantum charge transport in two-dimensional networks in the presence of a magnetic field and spin-orbit interaction. The interplay of the corresponding Abelian and non-Abelian gauge fields leads to an intricate behavior of the conductance, which has different periodicities in the diffusive and ballistic regimes. We classify all configurations of magnetic and spin-orbit fields where a logarithmically divergent weak-(anti)localization correction appears in the diffusive regime. The conductivity of topologically distinct configurations is the same in the diffusive regime but different in the ballistic regime. The proposed setup provides a feasible realization of quantum graphs with non-Abelian gauge fields.

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cond-mat.mes-hall cond-mat.dis-nn quant-ph

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A. V. Poshakinskiy, L. E. Golub. 2026-05-05. Coherent transport in non-Abelian quantum graphs. https://arxiv.org/abs/2605.03826

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