  Topological superconductors (TSCs) are unconventional superconductors with
bulk superconducting gap and in-gap Majorana states on the boundary that may be
used as topological qubits for quantum computation. Despite their importance in
both fundamental research and applications, natural TSCs are very rare. Here,
combining state of the art synchrotron and laser-based angle-resolved
photoemission spectroscopy, we investigated a stoichiometric transition metal
dichalcogenide (TMD), 2M-WS2 with a superconducting transition temperature of
8.8 K (the highest among all TMDs in the natural form up to date) and observed
distinctive topological surface states (TSSs). Furthermore, in the
superconducting state, we found that the TSSs acquired a nodeless
superconducting gap with similar magnitude as that of the bulk states. These
discoveries not only evidence 2M-WS2 as an intrinsic TSC without the need of
sensitive composition tuning or sophisticated heterostructures fabrication, but
also provide an ideal platform for device applications thanks to its van der
Waals layered structure.
