Microscopic Fingerprint of Chiral Superconductivity on a Silicon Surface

Chiral superconductors are predicted to break time-reversal symmetry and host topological excitations such as Majorana modes, yet direct evidence of chiral pairing has remained elusive. In this talk, I will present direct, real-space evidence of intrinsic chiral superconductivity in a single atomic layer of tin on Si(111). Using high-resolution quasiparticle interference imaging with scanning tunneling microscopy, we uncover that all impurity-bound states within the superconducting gap of Sn/Si(111) display an anomalous yet universal spatial pattern: the local density of states at the defect center vanishes at one bound-state energy but remains finite at its particle-hole conjugate. These spatially resolved node-antinode features, together with their surrounding texture, constitute a distinctive microscopic fingerprint of chiral d-wave pairing. I will further show analytically that this nodal impurity behavior emerges universally from the interplay between pairing chirality and crystalline rotational symmetry in generic two-dimensional chiral superconductors.