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arXiv · 1112.5326

Thermal expansion and Gr\"uneisen parameters of Ba(Fe1-xCox)2As2 - a thermodynamic quest for quantum criticality

Christoph Meingast·Frédéric Hardy·Rolf Heid·Peter Adelmann·Anna Böhmer·Philipp Burger·Doris Ernst·Rainer Fromknecht·Peter Schweiss·Thomas Wolf
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Abstract

Thermal expansion data are used to study the uniaxial pressure dependence of the electronic/magnetic entropy of Ba(Fe1-xCox)2As2. Uniaxial pressure is found to be proportional to doping and, thus, also an appropriate tuning parameter in this system. Many of the features predicted to occur for a pressure-tuned quantum critical system, in which superconductivity is an emergent phase hiding the critical point, are observed. The electronic/magnetic Gr\"uneisen parameters associated with the spin-density wave and superconducting transitions further demonstrate an intimate connection between both ordering phenomena.

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Christoph Meingast, Frédéric Hardy, Rolf Heid, Peter Adelmann, Anna Böhmer, Philipp Burger, Doris Ernst, Rainer Fromknecht, Peter Schweiss, Thomas Wolf. 2011-12-22. Thermal expansion and Gr\"uneisen parameters of Ba(Fe1-xCox)2As2 - a thermodynamic quest for quantum criticality. https://doi.org/10.1103/physrevlett.108.177004

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