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.
@article{arxiv.2303.05833,
title = {Chiral spin channels in curved graphene $pn$ junctions},
author = {Dario Bercioux and Diego Frustaglia and Alessandro De Martino},
journal= {arXiv preprint arXiv:2303.05833},
year = {2023}
}