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arXiv · 2610.28854

Two quantum skyrmions form a magnon Josephson junction

R. L. Silva
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Abstract

Two quantum skyrmions in a frustrated spin-$1/2$ magnet bind into a molecule, and the molecule acts as a magnon Josephson junction: the relative helicity $θ$ and the number $n$ of magnons transferred between them obey $H=E_Cn^2-W\cosθ$. DMRG on the $J_1$--$J_2$ triangular lattice gives $E_C$ as the curvature of the skyrmion energy at its natural size of seven flipped spins, and the measured helicity coherence fixes $W\simeq0.02J_1$, half the skyrmion--antiskyrmion tunnel splitting and independent of the anisotropy. Two helicity qubits side by side are thus strongly coupled by their own interaction.

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R. L. Silva. 2026-10-20. Two quantum skyrmions form a magnon Josephson junction. https://arxiv.org/abs/2610.28854

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