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arXiv · 0912.3546

Universal signatures of the metamagnetic quantum critical endpoint: Application to CeRu2Si2

F. Weickert·M. Brando·F. Steglich·P. Gegenwart·M. Garst
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Abstract

A quantum critical endpoint related to a metamagnetic transition causes distinct signatures in the thermodynamic quantities of a compound. We argue that, irrespective of the microscopic details of the considered material, the diverging differential susceptibility combined with the Ising symmetry of the endpoint give rise to a number of characteristic metamagnetic phenomena. In the presence of a magnetoelastic coupling, one finds a correspondence of susceptibility, magnetostriction and compressibility and, as a result, a pronounced crystal softening, a diverging Grueneisen parameter, a sign change of thermal expansion alpha(H), and a minimum in the specific heat coefficient gamma(H). We illustrate these signatures and their relation on the metamagnetic crossover at 8 T in the prototypical heavy-fermion system CeRu2Si2.

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F. Weickert, M. Brando, F. Steglich, P. Gegenwart, M. Garst. 2010-05-04. Universal signatures of the metamagnetic quantum critical endpoint: Application to CeRu2Si2. https://doi.org/10.1103/physrevb.81.134438

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