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Heavy fermion behavior of itinerant frustrated systems: beta-Mn, Y(Sc)Mn_{2} and LiV_{2}O_{4}$

C. Lacroix
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Abstract

These three metallic systems do not exhibit any magnetic ordering despite experiments show the existence of localized moments with large antiferromagnetic exchange: this is a consequence of the strong geometric frustration (Y(Sc)Mn_{2} and LiV_{2}O_{4} have the Pyrochlore structure, while beta-Mn has a more complicated frustrated structure). Another common feature is their very large specific heat coefficient γ=C/T (420 mJ mole^{-1} K^{-2} for LiV_{2}O_{4}). Several explanations have been proposed for this ''3d heavy fermion behavior'', including a 3d-Kondo effect. However the similarities between the three compounds indicate that frustration plays a big role. We propose a new model which takes into account the existence of two types of 3d-electrons (localized and itinerant) and a frustrated antiferromagnetic exchange between the localized 3d electrons.

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C. Lacroix. 2001-07-31. Heavy fermion behavior of itinerant frustrated systems: beta-Mn, Y(Sc)Mn_{2} and LiV_{2}O_{4}$. https://doi.org/10.1139/cjp-79-11-12-1469

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