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arXiv · 2303.05833

Chiral spin channels in curved graphene $pn$ junctions

Dario Bercioux·Diego Frustaglia·Alessandro De Martino
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Abstract

We show that the chiral modes in circular graphene $pn$ junctions provide an advantage for spin manipulation via spin-orbit coupling compared to semiconductor platforms. We derive the effective Hamiltonian for the spin dynamics of the junction's zero modes and calculate their quantum phases. We find a sweet spot in parameter space where the spin is fully in-plane and radially polarized for a given junction polarity. This represents a shortcut to singular spin configurations that would otherwise require spin-orbit coupling strengths beyond experimental reach.

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Dario Bercioux, Diego Frustaglia, Alessandro De Martino. 2023-03-10. Chiral spin channels in curved graphene $pn$ junctions. https://doi.org/10.1103/physrevb.108.115140

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