A phonon irreducible representations calculator

Abstract

The irreducible representation of band structure is important for physical properties. Based on phonopy and recently developed SpaceGroupIrep package, we developed a package PhononIrep, which can get the band irreducible representation for arbitrary $\mathbf{k}$ point at first-principles level. As an application, we for the first time predict the cubic crossing Dirac point can exist in conventional crystal phonon systems X${}_3$Y (X=Ti, Nb, Ta, Y=Au, Sb). We hope this package will facilitate phonon research in the future.

6 pages, 3 figures