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An unusual interplay among disorder, Kondo-effect and spin-glass behavior in the Kondo lattices, Ce$_2$Au$_{1-x}$Co$_x$Si$_3$

Subham Majumdar·E. V. Sampathkumaran·St. Berger·M. Della Mea·H. Michor·E. Bauer·M. Brando·J. Hemberger·A. Loidl
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Abstract

We report the results of magnetic measurements for the solid solution Ce$_2$Au$_{1-x}$Co$_x$Si$_3$. The results reveal that this solid solution is characterized by a magnetic phase diagram (plot of magnetic transition temperature versus $x$) unusual for Kondo lattices. In particular, the spin-glass freezing induced by disorder is observed only for the compositions at the weak coupling limit; as one approaches the quantum critical point by a gradual replacement of Au by Co, this disorder effect is surprisingly suppressed in favor of long range antiferro-magnetic ordering in contrast to expectations. This unusual interplay between disorder, spin-glass freezing and the Kondo-effect calls for further refinement of theories on competition between magnetism and the Kondo effect.

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Subham Majumdar, E. V. Sampathkumaran, St. Berger, M. Della Mea, H. Michor, E. Bauer, M. Brando, J. Hemberger, A. Loidl. 2002-03-30. An unusual interplay among disorder, Kondo-effect and spin-glass behavior in the Kondo lattices, Ce$_2$Au$_{1-x}$Co$_x$Si$_3$. https://doi.org/10.1016/s0038-1098(02)00053-4

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