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arXiv · 1403.6004

Searching for a quantum critical point in YbCu5-xAux

I. Čurlik·M. Reiffers·J. G. Sereni·M. Giovannini·S. Gabani
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Abstract

Structural, magnetic, transport and thermal properties of YbCu5-xAux alloys with Au concentration between the limit of structural stability of AuBe5 type at x = 0.4 up to x = 0.7 are reported. The outstanding features of this system are: i) the constant and record high values of Cm /T 7J/molK^2 below a characteristic temperature T*, ranging between 150 mK and 350 mK. ii) A power law thermal dependence dependence Cm/T(T>T*)=A/T^q, with q = 1.3 +/- 0.1, and iii) an arising incoherent electronic scattering observed in the resistivity at T < 1K for x < 0.6 despite the fact that Yb magnetic atoms are placed in a lattice. Magnetic frustration, originated in the tetrahedral distribution of Yb atoms, appears as the responsible of the exotic behavior of this system.

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I. Čurlik, M. Reiffers, J. G. Sereni, M. Giovannini, S. Gabani. 2014-03-24. Searching for a quantum critical point in YbCu5-xAux. https://arxiv.org/abs/1403.6004

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