Evidence of surface p-wave superconductivity and higher-order topology in MoTe₂

Exploration of nontrivial superconductivity and electronic band topology is at the core of condensed matter physics and applications to quantum information. The transition-metal dichalcogenide (TMDC) MoTe₂ has been proposed as an ideal candidate to explore the interplay between topology and superconductivity, but their studies remain limited because of the high-pressure environments required to control the topological phase transition. In this work, we demonstrate the tunable superconductivity and the resultant higher-order topology of MoTe₂ under extreme pressure. In the pressured Td phase, Andreev reflection spectroscopy reveals two-gap features, indicating that the Weyl fermions lead to a topological s±-wave multigap superconductivity. On the other hand, the high-pressure 1T$'$ phase presents p-wave surface superconductivity emergent from the second-order topological bands via the bulk-to-surface proximity effect. Our analysis suggests that the topological hinge states generated from second-order topological bands evolve into zero-energy Majorana hinge states in the second-order topological superconductor. These results demonstrate the potential realization of topological superconductivity in MoTe₂, thus opening a pathway for studying various topological natures of TMDC materials.