Magnetic anisotropy in 2H-NbSe_2 electron irradiated single crystals

摘要

The anisotropic magnetic properties of the metallic layered compound with hexagonal crystal structure 2H-NbSe_2 are investigated as a function of their dependence on high-energy electron irradiation. Pauli paramagnetism of free electrons is shown to dominate the magnetic susceptibility, Χ_p. The anisotropy is related to spin-orbit effects on the hybridized electronic states. Irradiation affects the density of states at the Fermi surface, increasing both Χ_p and the anisotropy. Below a threshold temperature, T_s=54 K, the paramagnetic contribution, which increases with the dose, is ascribed to dangling bonds, nanotubes and nanorods generated by irradiation.