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arXiv · 1405.0675

General properties of phase diagrams of heavy-fermion metals

V. R. Shaginyan·A. Z. Msezane·K. G. Popov·G. S. Japaridze·V. A. Khodel
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Abstract

We study the temperature-magnetic field T-B phase diagrams of heavy fermion (HF) metals, and show that at sufficiently high temperatures outside the ordered phase the crossover temperature T*(B), regarded as the energy scale, follows a linear B-dependence, crossing the origin of the T-B phase diagram. This behavior of T*(B) constitutes the general property, and is formed by the presence of fermion condensation quantum phase transition hidden within the ordered phase. Our result is in good agreement with the experimental T-B phase diagram of the HF metals YbRh2Si2, Yb(Rh{0.93}Co{0.07})2Si2, and Yb(Rh{0.94}Ir{0.06})2Si2. To support our observations, we analyze the isothermal magnetization M, and demonstrate that dM/dT exhibits a universal temperature behavior over magnetic field scaling. The obtained results are in good agreement with the corresponding data collected on YbRh2Si2 as a function of magnetic field at different temperatures under hydrostatic pressure.

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V. R. Shaginyan, A. Z. Msezane, K. G. Popov, G. S. Japaridze, V. A. Khodel. 2014-05-04. General properties of phase diagrams of heavy-fermion metals. https://doi.org/10.1209/0295-5075%2F106%2F37001

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