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arXiv · 1207.4411

From incommensurate correlations to mesoscopic spin resonance in YbRh2Si2

C. Stock·C. Broholm·F. Demmel·J. Van Duijn·J. W. Taylor·H. J. Kang·R. Hu·C. Petrovic
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Abstract

Spin fluctuations are reported near the magnetic field driven quantum critical point in YbRh2Si2. On cooling, ferromagnetic fluctuations evolve into incommensurate correlations located at q0=+/- (delta,delta) with delta=0.14 +/- 0.04 r.l.u. At low temperatures, an in plane magnetic field induces a sharp intra doublet resonant excitation at an energy E0=g muB mu0 H with g=3.8 +/- 0.2. The intensity is localized at the zone center indicating precession of spin density extending xi=6 +/- 2 A beyond the 4f site.

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C. Stock, C. Broholm, F. Demmel, J. Van Duijn, J. W. Taylor, H. J. Kang, R. Hu, C. Petrovic. 2012-07-18. From incommensurate correlations to mesoscopic spin resonance in YbRh2Si2. https://doi.org/10.1103/physrevlett.109.127201

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