Field-induced suppression of the heavy-fermion state in YbRh2Si2.
We report dc-magnetization measurements on YbRh2Si2 at temperatures down to 0.04 K, magnetic fields B< or =11.5 T, and under hydrostatic pressure P< or =1.3 GPa. At ambient pressure a kink at B* =9.9 T 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.
Tokiwa
Y
Y
Max-Planck-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany.
Gegenwart
P
P
Radu
T
T
Ferstl
J
J
Sparn
G
G
Geibel
C
C
Steglich
F
F