NMR Studies on Magnetic Properties of ZrZn₂

Abstract

The temperature and external field dependences of ⁹¹Zr nuclear magnetic resonance (NMR) in ZrZn₂ have been measured in the respective range from 1.4 to 300 K and from 25 to 90 kOe. From the diagram of the Knight shift K(T) vs susceptibility χ(T), the hyperfine field due to d-spin, H_hf(d), and the orbital contributions to the Knight shift and the susceptibility, K_orb and χ_orb, were determined to be −27.5 kOe/μ_B, 0.59% and 32.4×10²⁹ emu/atom, respectively. The d-spin contribution to the susceptibility χ_d(T) was also obtained. The external field dependence of the internal field at ⁹¹Zr, H_i^Zr, in the ferromagnetic state was analyzed in terms of the hyperfine fields proportional to d-moment and to external field H₀. This gives −3.30 kOe for H_i^Zr extrapolated to H₀=0 and −25.3 kOe/μ_B for H_hf(d).