Electronic and topological characters of the ideal magnetic topological materials EuAuX with X = P, As, Sb, and Bi

Ideal magnetic topological materials have great significance in both fundamental physics and technical applications, due to their abundant exotic quantum properties and facilitation of control. Using first-principles calculations, we find several ideal magnetic topological materials in EuTX (T = Cu, Ag, and Au; X= P, As, Sb, and Bi) family. Particularly, EuAuP is the ferromagnetic Weyl semimetal, and EuAuX (X = As, Sb, and Bi) in their ground state with in-plane moments are the antiferromagnetic semimetals hosting the topological gap near the Fermi level. By tuning the magnetic moments to z -axis, EuAuX (X = As, Sb, and Bi) could further evolve into triple degenerate nodal points (TDNPs) semimetal states. The main characteristics of antiferromagnetic TDNP semimetal, including the Fermi arcs, and touching Fermi surfaces with opposite spin winding numbers, are also studied. Our work provides an ideal and reliable platform to modulate the magnetism, topological electronic structures and emergent quantum states.