  The prediction of non-trivial topological electronic states hosted by
half-Heusler compounds makes them prime candidates for discovering new physics
and devices as they harbor a variety of electronic ground states including
superconductivity, magnetism, and heavy fermion behavior. Here we report normal
state electronic properties of a superconducting half-Heusler compound YPtBi
using angle-resolved photoemission spectroscopy (ARPES). Our data reveal the
presence of a Dirac state at the zone center of the Brillouin zone at 500 meV
below the chemical potential. We observe the presence of multiple Fermi surface
pockets including two concentric hexagonal and six half oval shaped pockets at
the gamma and K points of the Brillouin zone, respectively. Furthermore, our
measurements show Rashba-split bands and multiple surface states crossing the
chemical potential which are supported by the first-principles calculations.
Our finding of a Dirac state in YPtBi plays a significant role in establishing
half-Heusler compounds as a new potential platform for novel topological phases
and explore their connection with superconductivity.
