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arXiv · 1307.2412

Spin-Density-Wave-Type Ordering of LaCoGe Revealed by ^{59}Co- and ^{139}La-Nuclear Magnetic Resonance Measurements

Kosuke Karube·Taisuke Hattori·Kenji Ishida·Nobuyuki Tamura·Kazuhiko Deguchi·Noriaki K. Sato
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Abstract

The low-temperature magnetic properties of LaCoGe with the tetragonal CeFeSi-type structure were investigated by ^{59}Co- and ^{139}La-nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) measurements. The nuclear spin-lattice relaxation rate divided by the temperature, 1/(T_1 T), gradually increases with decreasing temperature and shows a kink at approximately 18 K, below which an inhomogeneous internal field appears at the Co nuclear site. These results indicate that antiferromagnetic ordering occurs below T_N ~ 18 K. However, an internal field was not observed at the La nuclear site below T_N. Taking all NMR results into account, we conclude that spin-density-wave (SDW)-type ordering occurs, where magnetic correlations are of the checkerboard type in the ab-plane and have a long periodicity along the c-axis with inhomogeneous ordered moments pointing to the c-axis.

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Kosuke Karube, Taisuke Hattori, Kenji Ishida, Nobuyuki Tamura, Kazuhiko Deguchi, Noriaki K. Sato. 2013-07-09. Spin-Density-Wave-Type Ordering of LaCoGe Revealed by ^{59}Co- and ^{139}La-Nuclear Magnetic Resonance Measurements. https://doi.org/10.7566/jpsj.82.083712

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