The field of topological materials is developing rapidly, exhibiting new physical phenomena and inviting potential applications in the emerging fields of quantum computing and sensing. The materials chemistry challenge is to identify and synthesize materials falling into each of the predicted topological classes. Normally, the maximal degeneracy of states in any electronic system is six (three degenerate orbitals). Topological considerations predict that in certain materials the double group cross product of two irreducible representations (irreps.) or the cross product of one irrep. on itself can yield eight states that are degenerate in energy at a high symmetry point in reciprocal space. Materials including CuBi2O4 and PdBi2O4 are theorized to be such 8-fold fermion or double Dirac systems on the basis of their symmetries. However, their insulating behavior hinders photoemission and transport characterizations, which are crucial for unambiguous identification. Here we present our strategy for designing real materials with 8-fold fermions based on chemical principles, and provide an update on experimental detection of this novel topological state.

In pursuit of double dirac fermions

Macromolecular Chemistry: The Second Century

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ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.