B-11 NMR study of HoNi2B2C

Abstract

B-11 nuclear magnetic resonance (NMR) measurements have been performed at 8 T to study 4f spin dynamics in two single crystals of HoNi2B2C. The first crystal turns out to be of a poor quality showing an unaligned part of crystallites. On the other hand, the second sample shows a high quality with large anisotropy of shift for field parallel and perpendicular to the c-axis. Also, B-11 NMR spectra are extremely broad. Both shift and linewidth are highly temperature dependent. Furthermore, the spin-lattice and the spin-spin relaxation times are extremely short and strongly anisotropic. All these features indicate that the 4f spin fluctuation in HoNi2B2C is significant and highly anisotropic. The anisotropy of the NMR shift and the relaxation times as well as its temperature dependence can be analyzed to understand microscopic details of the 4f spin dynamics. (C) 2003 Elsevier B.V. All rights reserved.