ARPES Evidence for i-Wave Topological Superconductivity in the Fermi Arc States of t-PtBi₂

Topological superconductivity is a key ingredient for realizing Majorana fermions, yet intrinsic material platforms remain scarce. Using angle-resolved photoemission spectroscopy (ARPES), we have recently demonstrated that the Weyl semimetal t-PtBi₂ hosts superconductivity confined to its topological surface states, the Fermi arcs [1]. This superconductivity is unconventional, with nodal i-wave symmetry and signatures of emergent Majorana modes [2], and can be robustly detected under both laser- and synchrotron-based ARPES conditions [3]. Moreover, t-PtBi₂ fulfills the canonical criteria favorable for high-Tc superconductivity, opening the door to tuning and optimizing this exotic state [4]. These findings establish t-PtBi₂ as a rare platform where ARPES directly reveals superconductivity of topological surface states, paving the way toward intrinsic realizations of Majorana physics.