https://doi.org/10.1007/s100510050520
Pressure-induced magnetically ordered Kondo lattice state in YbCu2Si2
University of Geneva, DPMC, 24 quai Ernest-Ansermet,
1211 Geneva 4, Switzerland
Corresponding author: a khalid.alami-yadri@physics.unige.ch
Received:
29
December
1997
Revised:
7
July
1998
Accepted:
10
July
1998
Published online: 15 November 1998
The effect of pressure on the electrical resistivity ρ(T) of several YbCu2Si2 samples was investigated up to 25 GPa and for 30 mK < T < 300 K. With increasing pressure the compound crosses from an intermediate valence state to a magnetic Kondo lattice state at a critical pressure PC ~ 8 GPa. Below PC, i.e. in the non-magnetic phase, ρ = ρ0 + AT2 is found at very low temperature, indicating the validity of the Fermi liquid description. On approaching the magnetic instability, the A coefficient and the residual resistivity ρ0 increase strongly. Close to PC, ρ0 shows a pronounced maximum due to scattering by lattice defects. The pressure variation of the magnetic resistivity ρmag at high temperature is interpreted in the terms of a pressure induced change of the crystal field splitting.
PACS: 67.55.Hc – Transport properties / 71.27.+a – Strongly correlated electron systems; heavy fermions / 72.10.Fk – Scattering by point defects, dislocations, surfaces, and other imperfections (including Kondo effect) / 75.30.Mb – Valence fluctuation, Kondo lattice, and heavy-fermion phenomena
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998