Nuclear Magnetic Resonance of Au¹⁹⁷ in the Ordered Ferromagnetic Alloy Au₄Mn

Abstract

The hyperfine field at Au¹⁹⁷ nuclei in Au₄Mn has been measured using the spin echo technique. A broad Au¹⁹⁷ resonance with a complicated line shape is observed between 60 and 73 MHz in zero applied magnetic field at 1.7 K. The line shape which depends on the applied magnetic field is interpreted as due to the presence of an anisotropic hyperfine interaction. The isotropic hyperfine field at Au¹⁹⁷ is determined to be −933 kOe. The zero-field Mn⁵⁵ resonance is also observed at 440 MHz at 1.7 K. The magnitude of corresponding hyperfine field is 420 kOe.