Controllable synthesis and magnetotransport properties of Cd3As2 Dirac semimetal nanostructures

Abstract

Cd₃As₂, known as the three-dimensional (3D) analogue of graphene, is a Dirac semimetal with a linear dispersion relation along all three directions in momentum space. Here, Cd₃As₂ nanostructures with various morphologies, including nanowires, nanobelts, nanoplates and nano-octahedra, were synthesized by a facile chemical vapour deposition method. All these kinds of morphologies can be synthesised by carefully adjusting the pressure and argon flow rate. Further, we systematically investigated the magnetotransport properties of the as-grown nanostructures. The temperature dependences of resistance all displayed insulating behaviour, indicating the low carrier density and the Fermi level close to the Dirac point in our Cd₃As₂ nanostructures. All nanodevices hosted the unsaturated magnetoresistance even up to 14 T. The linear magnetoresistance was observed in nanodevices based on nanoribbons and nanowires. Our detailed study on the morphology regulation and magnetotransport properties of Cd₃As₂ nanostructures is valuable for the understanding of the growth process and the future nanoelectronic applications of 3D Dirac semimetals.