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arXiv · 1204.4632

Magnetic order and spin dynamics in the proximity of a ferromagnetic quantum critical point: A {\mu}SR study of YbNi4P2

J. Spehling·M. Günther·C. Krellner·N. Yèche·H. Luetkens·C. Baines·C. Geibel·H. -H. Klauss
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Abstract

The local 4f-electronic spin dynamics and magnetic order in YbNi4P2 were studied by means of muon-spin relaxation measurements. Zero-field muon-spin relaxation proves static magnetic order with a strongly reduced ordered Yb3+ moment of (2.5-4.6) \times 10-2{\mu}B, below TC = 140 mK. Above TC, the muon-spin polarization P(t,B) is dominated by quasihomogeneous spin fluctuations and exhibits a time-field scaling relation P(t,B) = P(t/B{\gamma}), indicating cooperative critical spin dynamics in the system. At T = 190 mK, slightly above TC, {\gamma} = 0.81(5), suggesting time-scale invariant power-law behavior for the dynamic electronic spin-spin autocorrelation function.

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J. Spehling, M. Günther, C. Krellner, N. Yèche, H. Luetkens, C. Baines, C. Geibel, H. -H. Klauss. 2012-04-20. Magnetic order and spin dynamics in the proximity of a ferromagnetic quantum critical point: A {\mu}SR study of YbNi4P2. https://doi.org/10.1103/physrevb.85.140406

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