Microscopic Fingerprint of Chiral Superconductivity

Xuefeng Wu; Xuan Hao; Zhuo Chen; Yuchang Cai; Minghao Wu; Congrun Chen; Kedong Wang; Fangfei Ming; Steven Johnston; Rui-Xing Zhang; Hanno H. Weitering

arXiv · 2507.18693

Microscopic Fingerprint of Chiral Superconductivity

Xuefeng Wu·Xuan Hao·Zhuo Chen·Yuchang Cai·Minghao Wu·Congrun Chen·Kedong Wang·Fangfei Ming·Steven Johnston·Rui-Xing Zhang·Hanno H. Weitering

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Abstract

Chiral superconductors have long been theorized to break time-reversal symmetry and support exotic topological features such as Majorana modes and spontaneous edge currents, promising ingredients for quantum technologies. Although several unconventional superconductors may exhibit time-reversal symmetry breaking, clear microscopic evidence of chiral pairing has remained out of reach. In this work, we demonstrate direct real-space signatures of chiral superconductivity in a single atomic layer of tin on Si(111). Using quasiparticle interference imaging, we detected symmetry-locked nodal and antinodal points in the Bogoliubov quasiparticle wavefunction, tightly bound to atomic point defects in the tin lattice. These nodal features, along with their surrounding texture, form a distinct real-space pattern exhibiting a clear and exclusive hallmark of chiral superconductivity. Our findings, reinforced by analytical theory and numerical simulations, offer unambiguous evidence of chiral pairing in a two-dimensional material.

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Xuefeng Wu, Xuan Hao, Zhuo Chen, Yuchang Cai, Minghao Wu, Congrun Chen, Kedong Wang, Fangfei Ming, Steven Johnston, Rui-Xing Zhang, Hanno H. Weitering. 2025-07-24. Microscopic Fingerprint of Chiral Superconductivity. https://arxiv.org/abs/2507.18693

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