[Zurück]

S. Majumdar, E.V. Sampathkumaran, St Berger, M. Della Mea, H. Michor, E. Bauer, M. Brando, J. Hemberger, A. Loidl:
"Spin-glass, antiferromagnetism and Kondo behavior in Ce₂Au_1-xCo_xSi₃ alloys";
Pramana - Journal of Physics, Vol. 58 (2002), 5 & 6; S. 777 - 782.

Spin-glass, antiferromagnetism and Kondo behavior in Ce2Au1-xCoxSi3 alloys

SUBHAM MAJUMDAR1, E V SAMPATHKUMARAN1,, ST BERGER2, M DELLA MEA2,H MICHOR2, E BAUER2, M BRANDO3, J HEMBERGER3 and A LOIDL3

1Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India
2Institute for Experimental Physics, Vienna University of Technology, A-1040 Wien, Austria
3Experimentalphysik V, Electronische Korrelationen und Magnetismus, Institut f¨ur Physik, Universit¨at Augsburg, D-86135 Augsburg, Germany
Email: sampath@tifr.res.in

Abstract
Recently, the solid solution Ce2Au1xCox Si3 has been shown to exhibit many magnetic anomalies associated with the competition between magnetic ordering and the Kondo effect. Here we report high pressure electrical resistivity of Ce2AuSi3, ac susceptibility (?) and magnetoresistance of various alloys of this solid solution in order to gain better knowledge of the magnetism of these alloys. High pressure resistivity behavior is consistent with the proposal that Ce2AuSi3 lies at the left-hand side of the maximum in Doniach?s magnetic phase diagram. The ac ? data reveal that there are in fact two magnetic transitions, one at 2 K and the other at 3 K for this compound, both of which are spin-glass-like. However, as the Co concentration is increased, antiferromagnetism is stabilized for intermediate compositions before attaining non-magnetism for the Co end member. Keywords. Ce2Au1xCox Si3 alloy; spin-glass; antiferromagnetism; Kondo behaviour; magnetoresistance.

http://www.ias.ac.in/pramana/mayjune2002/as10.pdf