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Field-induced suppression of the heavy-fermion state in YbRh_2Si_2

Y. Tokiwa·P. Gegenwart·T. Radu·J. Ferstl·G. Sparn·C. Geibel·F. Steglich
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Abstract

We report DC magnetization measurements on YbRh_2Si_2 at temperatures down to 0.04K, magnetic fields B<11.5T and under hydrostatic pressure P<1.3GPa. At ambient pressure a kink at B*=9.9T indicates a new type of field-induced transition from an itinerant to a localized 4f-state. This transition is different from the metamagnetic transition observed in other heavy fermion compounds, as here ferromagnetic rather than antiferromagnetic correlations dominate below B*. Hydrostatic pressure experiments reveal a clear correspondence of B* to the characteristic spin fluctuation temperature determined from specific heat.

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Y. Tokiwa, P. Gegenwart, T. Radu, J. Ferstl, G. Sparn, C. Geibel, F. Steglich. 2013-06-22. Field-induced suppression of the heavy-fermion state in YbRh_2Si_2. https://doi.org/10.1103/physrevlett.94.226402

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