  Topological semimetal is a topic of general interest in material science.
Recently, a new kind of topological semimetal called type-II Dirac semimetal
with tilted Dirac cones is discovered in PtSe2 family. However, the further
investigation is hindered due to the huge energy difference from Dirac points
to Fermi level and the irrelevant conducting pockets at Fermi surface. Here we
characterize the optimized type-II Dirac dispersions in a metastable 1T phase
of IrTe2. Our strategy of Pt doping protects the metastable 1T phase in low
temperature and tunes the Fermi level to the Dirac point. As demonstrated by
angle-resolved photoemission spectra and first principle calculations, the
Fermi surface of Ir1-xPtxTe2 is formed by only a single band with type-II Dirac
cone which is tilted strongly along kz momentum direction. Interesting
superconductivity is observed in samples for Dirac point close to Fermi level
and even survives when Fermi level aligns with the Dirac point as finite
density of states created by the tilted cone dispersion. This advantage offers
opportunities for possible topological superconductivity and versatile Majorana
devices in type-II Dirac semimetals.
