Dirac and Weyl semimetals both exhibit arclike surface states. However, whereas the surface Fermi arcs in Weyl semimetals are topological consequences of the Weyl points themselves, the surface Fermi arcs in Dirac semimetals are not directly related to the bulk Dirac points, raising the question of whether there exists a topological bulkboundary correspondence for Dirac semimetals. In this work, we discover that strong and fragile topological Dirac semimetals exhibit onedimensional (1D) higherorder hinge Fermi arcs (HOFAs) as universal, direct consequences of their bulk 3D Dirac points. To predict HOFAs coexisting with topological surface states in solidstate Dirac semimetals, we introduce and layer a spinful model of an
Twodimensional (2D) Dirac states with linear dispersion have been observed in graphene and on the surface of topological insulators. 2D Dirac states discovered so far are exclusively pinned at highsymmetry points of the Brillouin zone, for example, surface Dirac states at
 Publication Date:
 NSFPAR ID:
 10381741
 Journal Name:
 Nature Communications
 Volume:
 13
 Issue:
 1
 ISSN:
 20411723
 Publisher:
 Nature Publishing Group
 Sponsoring Org:
 National Science Foundation
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