Low Carrier Density Metal Realized in Candidate Line-Node Dirac Semimetals CaAgP and CaAgAs

Abstract

We study polycrystalline samples of the hexagonal pnictides, CaAgP and CaAgAs, both of which are ideal candidates for line-node Dirac semimetals. The polycrystalline samples of CaAgP and CaAgAs obtained in this study are low-carrier metals, where hole carriers are dominant. By combining the hole carrier densities estimated from Hall coefficients and the electronic structures calculated by first principles calculations, both samples are found to have a ring-torus Fermi surface, derived from a ring-shaped Dirac line node. In the phosphide sample, the Fermi energy EF is located at around the end of the linear dispersion region of the electronic bands, while the EF in the arsenide sample exists in the middle of this region, suggesting that the arsenide is a more promising system for uncovering the physics of line-node Dirac semimetals.

6 pages, 5 figures

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Cited by in corpus (7)

• Observation of Dirac-like energy band and ring-torus Fermi surface associated with the nodal line in topological insulator CaAgAs
• Flat optical conductivity in ZrSiS due to two-dimensional Dirac bands
• Hybrid Dirac Semimetal in CaAgBi Materials Family
• Topological surface superconductivity in doped Weyl loop materials
• Universal phase transition and band structures for spinless nodal-line and Weyl semimetals
• Nodal-line semimetals from Weyl superlattices
• Unusual Resistive Transitions in the Nodal-Line Semimetallic Superconductor NaAlSi