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arXiv · 1201.3260

^31P NMR investigations on the ferromagnetic quantum critical system YbNi_4P_2

R. Sarkar·P. Khuntia·C. Krellner·C. Geibel·F. Steglich·M. Baenitz
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Abstract

We studied the new heavy-fermion system YbNi$_{4}$P$_{2}$, which presents strong ferromagnetic correlations, using the local $^{31}$P NMR probe over a wide field (0.2-8.6 \textsf{T}) and temperature (1.8-200 K) range. $^{31}$P NMR Knight shift provides the static spin susceptibility which tracks the bulk susceptibility whereas the spin-lattice relaxation rate $^{31}(1/T_{1}$) provide information about the fluctuations of the Yb 4f moment. The Korringa law is valid over a wide range in temperature and field. The Korringa product $^{31}(1/T_{1}TK^{2}$S$_{0}$) $\ll$ 1 gives evidence for the presence of strong ferromagnetic correlations. Over two decades in temperature a $^{31}(1/T_{1}T) \sim T^{-3/4}$ behaviour was found.

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R. Sarkar, P. Khuntia, C. Krellner, C. Geibel, F. Steglich, M. Baenitz. 2012-01-16. ^31P NMR investigations on the ferromagnetic quantum critical system YbNi_4P_2. https://doi.org/10.1103/physrevb.85.140409

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