Physical properties and first-principles calculations of an altermagnet candidate Cs$_{1-δ}$V$_2$Te$_2$O

Chang-Chao Liu; Jing Li; Ji-Yong Liu; Jia-Yi Lu; Hua-Xun Li; Yi Liu; Guang-Han Cao

doi:10.1103/vch1-4khc

paper

Physical properties and first-principles calculations of an altermagnet candidate Cs $_{1 - δ}$ V $_{2}$ Te $_{2}$ O

arXiv:2511.06865 · doi:10.1103/vch1-4khc

Abstract

We report the crystal growth, structure, physical properties, and first-principles calculations of a vanadium-based oxytelluride Cs $_{1 - δ}$ V $_{2}$ Te $_{2}$ O. The material possesses two-dimensional V $_{2}$ O square nets sandwiched by tellurium layers, with local crystallographic symmetry satisfying the spin symmetry for a $d$ -wave altermagnet. An antiferromagnetic transition at 293 K is unambiguously evidenced from the measurements of magnetic susceptibility and specific heat. In addition, a secondary transition at $\sim$ 70 K is also observed, possibly associated with a Lifshitz transition. The first-principles calculations indicate robust Néel-type collinear antiferromagnetism in the V $_{2}$ O plane. Consequently, spin splittings show up in momentum space, in relation with the real-space mirror/rotation symmetry. Interestingly, the V- $d_{y z} / d_{x z}$ electrons, which primarily contribute the quasi-one-dimensional Fermi surface, turns out to be fully orbital- and spin-polarized, akin to the case of a half metal. Our work lays a solid foundation on the potential applications utilizing altermagnetic properties in vanadium-based oxychalcogenides.

10 pages, 7 figures, and 2 tables

Physical properties and first-principles calculations of an altermagnet candidate Cs1−δ​V2​Te2​O

Abstract

References in corpus (19)

Physical properties and first-principles calculations of an altermagnet candidate Cs $_{1 - δ}$ V $_{2}$ Te $_{2}$ O