CuP: a new type of anisotropic and very stable Dirac cone material

Abstract The anisotropic Dirac cone has the advantage of anisotropic carrier mobility, which is different from other Dirac materials and can be applied to direction-dependent quantum devices. By first-principle calculation, we systematically research the Dirac cone and quantum properties of CuP. The calculation results show that CuP monolayer is a new type of anisotropic Dirac material. In addition, there is no virtual frequency in the phonon spectrum of this structure. At 300 K, the CuP monolayer can be remained well and there is no loose fracture of the structure. Based on grounds of Born criteria, CuP monolayer has good mechanical stability. Interestingly, considering the effect of spin-orbit coupling (SOC), the Dirac cone does not open the band gap. Moreover, the addition of stress does not destroy the Dirac cone. The material is mechanically and thermally stable. The results of Poisson's ratio and Young's modulus show that the structure has obvious anisotropy. It is worth noting that, the Fermi velocity to the right is 2.3 × 105 m/s and the left is 4.5 × 105 m/s, which is in the same order of magnitude as the Fermi velocity of graphene (8.0 × 105 m/s). The calculation results provide an ideal basis for the design of directional electron transport devices in spintronics.