Extended Data Fig. 2: Topological invariants and surface states of Zr(TiH2)2.

a, Brillouin zone for Zr(TiH2)2, in which the yellow plane is \({m}_{1\bar{1}0}\). b, Wilson loop for Zr(TiH2)2 in the \({m}_{1\bar{1}0}\) plane. c, One-dimensional helical modes in a cubic Zr(TiH2)2 sample. d, Two-dimensional surface states on each surface of a cubic Zr(TiH2)2 sample.