NMR 63.65Cu in a Local Field and Relaxation of Nuclear Spins in a CuFeS2 Magnetic Semiconductor

Abstract

The results of the study of the spectral and relaxation parameters of Cu-63.65 nuclear magnetic resonance (NMR) in a local field in natural samples of the semiconductor mineral chalcopyrite (CuFeS2), which is characterized by a strong interplay of magnetic and electronic properties, are presented. The main attention was paid to the determination of the mechanism of nuclear spin-lattice relaxation. The well-resolved quadrupole structure of the Cu-63.65 NMR spectrum allowed us to investigate the kinetics of nuclear magnetization recovery for both Cu isotopes. The magnetic mechanism of the spin-lattice relaxation of the nuclear spins of copper isotopes Cu-63.65 in CuFeS2, due to fluctuations of the dipole local fields created by the electron spins of magnetic Fe3+ ions, has been determined.