PtBi₂ is a promising platform for topological superconductivity, with the strongest evidence coming from angle-resolved photoemission spectroscopy (ARPES). I will show that in the non-centrosymmetric Weyl semimetal and van der Waals material PtBi₂, superconductivity is intrinsically confined to the surface: below about 20 K, ARPES detects a gap opening selectively on the topological Fermi-arc states, while the bulk-derived states remain completely ungapped in ARPES and the bulk remains normal in bulk-sensitive measurements. High-resolution ARPES further points to a nodal gap structure, consistent with unconventional pairing and a topological superconducting surface state. Because these surface states arise from the bulk Weyl topology, PtBi₂ provides an intrinsic interplay of bulk topology and surface superconductivity and may represent a rare case of superconductivity confined to the surface alone. A diamagnetic response appears in the same temperature range only in AC susceptibility, not in the DC Meissner signal, indicating strong superconducting fluctuations. These persist to low temperatures and are also observed by scanning SQUID microscopy. STM reveals the remarkable potential of this system, with some surfaces showing very large gap values, high apparent transition temperatures, and high critical fields. Superconductivity is also found in nanoscale exfoliated flakes, where it depends strongly on sample dimensions, consistent with a surface-dominated state. At the same time, STM and scanning SQUID reveal strong variations between different surfaces, indicating sensitivity to local surface conditions, possibly influenced by defects, strain, or morphology. Theory further suggests that the i-wave state intrinsically involves both non-equivalent surfaces. PtBi₂ thus emerges as a compelling but complex candidate for intrinsic topological surface superconductivity.

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