Nuclear Magnetic Resonance and Relaxation of ¹⁵⁹Tb in Ferromagnetic Terbium Metal

Abstract

Nuclear magnetic resonance and relaxation of ¹⁵⁹Tb in ferromagnetic Tb metal were investigated by spin echo technique at liquid helium temperatures. The nuclear magnetic resonance spectrum consists of three equally separated lines in the frequency range from 2.4 GHz to 3.9 GHz. The center line frequency which corresponds to the Zeeman frequency is 3120 MHz and the frequency difference of the adjacent lines which represents the electric quadrupole effect is 673.5 MHz. It is found that spin-lattice relaxation is produced mainly by the process in which the nuclear energy relaxes to the kinetic energy of the conduction electrons via spin waves (Weger’s mechanism), as in the case of Dy nuclei in ferromagnetic Dy metal, and the spin-spin relaxation time is determined by the spin-lattice relaxation and the I·I coupling.