Half-metallic ferromagnetism in transition-metal encapsulated boron nitride nanotubes

Abstract

We have studied zig-zag boron nitride (BN) nanotubes filled with the Ni hexagonal-close-packed nanowire. The Ni/BN nanotube hybrid structures are ferromagnetic metals with substantial magnetism. Some special magnetic properties resulting from the interaction between the Ni nanowire and BN nanotubes are found. The Ni encapsulated BN(9,0) nanotube shows semi-half-metallic behaviour, which can become half-metallic after doping electrons more than 1.4 e per unit cell. The intrinsic half-metallic behaviour can be achieved in two different ways: one is by coating the Ni nanowire with a smaller BN nanotube, i.e., BN(8,0), and the other is using hydrostatic pressure to homogeneously compress the Ni encapsulated BN(9,0) nanotube.