The de Haas-van Alphen quantum oscillations in a three-dimensional Dirac semimetal TiSb2

Characterization of the Fermi surface of high-quality crystalline TiSb2 by de Haas-van Alphen measurement reveals nontrivial topological properties. Moreover, our analysis of the quantum oscillation frequencies associated with nonzero Berry phase when the magnetic field is parallel to both the ab-plane and c-axis of TiSb2 finds that the Fermi surface topology has a three-dimensional feature. The results are supported by first-principle calculations which reveal a symmetry-protected Dirac point along the Γ-Z high symmetry line near the Fermi level. On the (001) surface, the bulk Dirac points are found to project onto the Γ ¯ point with nontrivial surface states. Our finding will substantially enrich the family of 3D Dirac semimetals which are useful for topological applications.