  In this study, two ideal triple degenerate point (TDP) semimetals were
predicted, namely, HfIrAs and HfIrBi, that exhibit clean TDPs around the fermi
level. At the atomic level, the origin of the TDP was analyzed, and when
combined with the low-energy effective 4-band model, it was found that the bulk
inversion asymmetry directly determines the formation of the TDP for cubic
crystals. The projected surface states and corresponding patterns of the fermi
arcs with and without tensile strain were investigated for two different
crystal face orientations [(111) and (110)], both of which could be detected
using photoemission spectroscopy. In addition, the disappearance of the spin
texture, which was studied in strained HgTe bulk states, was also observed in
the surface states. The results of this study indicate that the two materials
are unique platforms on which emergent phenomena, such as the interplay between
the TDP of semimetals and superconductivity, can be explored.
