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arXiv · 1003.2143

Effect of chemical substitution and pressure on YbRh2Si2

M. Nicklas·M. E. Macovei·J. Ferstl·C. Krellner·C. Geibel·F. Steglich
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Abstract

We carried out electrical resistivity experiments on (Yb,La)Rh2Si2 and on Yb(Rh,Ir)2Si2 under pressure and in magnetic fields. YbRh2Si2 exhibits a weak antiferromagnetic transition at atmospheric pressure with a Néel temperature of only T_N = 70 mK. By applying a small magnetic field T_N can be continuously suppressed to T=0 at B_c = 60 mT (B_|_c) driving the system to a quantum critical point (QCP). On applying external pressure the magnetic phase is stabilized and T_N(p) is increasing as usually observed in Yb-based heavy-fermion metals. Substituting Yb by La or Rh by Ir allows to create a negative chemical pressure, La (Ir) being smaller than Yb (Rh), and eventually to drive YbRh2Si2 to a pressure controlled QCP. In this paper we compare the effect of external hydrostatic pressure and chemical substitution on the ground-state properties of YbRh2Si2.

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M. Nicklas, M. E. Macovei, J. Ferstl, C. Krellner, C. Geibel, F. Steglich. 2010-03-10. Effect of chemical substitution and pressure on YbRh2Si2. https://doi.org/10.1002/pssb.200983064

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