Magnetic Anisotropy of CoS₂–Torque and NMR Measurements

Abstract

The magnetocrystalline anisotropy of CoS 2 has been measured by torque method using a single crystal and the anisotropy constants determined as K 1 <0 and K 2 ≃0, with the easy axis of [111]. The temperature dependence of K 1 is found to be proportional to the 20-th power of the thermomagnetic curve. The Co 59 NMR has been studied by both CW and transient techniques in the temperature range of 4.2–77 K. The NMR spectrum is broadened by an anisotropic hyperfine interaction, and the isotropic and axial components of the hyperfine field are determined to be -59.43 kOe and -5.42 kOe at 4.2 K. The overall resonance spectrum is explained qualitatively from the domain structure with the shape anisotropy. Some discussion of the electronic origin of the magnetic anisotropy is given.