Quantum oscillations and topological properties of a YB2 single crystal

The search for ideal quantum materials with symmetry-protected topological states continues to intrigue intense research activities in condensed matter physics. Here, we present single crystal growth, Fermi surface studies, and topological state analysis of a binary boride YB₂ that crystallizes in the hexagonal crystal structure with space group P6/mmm and lattice constants a=3. 304 (2), c=3. 846 (5). The single crystal of YB₂ was grown by the Czochralski method, in a tetra-arc furnace. The anisotropic physical properties are reported by performing the electrical transport and magnetization measurements. The electrical resistivity confirms the metallic nature of YB₂ while the magnetization reveals that it is a diamagnetic material. Interestingly in the magnetoresistance and magnetization measurements, we observe quantum oscillations, namely, Shubnikov-de Haas (SdH) oscillations and de Haas van Alphen (dHvA) oscillations for the magnetic field direction parallel to 0001. The quantum oscillations likely originates from a hole pocket centered at the A point. Our first-principles results unveil that YB₂ exhibits bulk nodal lines with interesting drumhead topological surface states.