Constraints on the merging of the transition lines at the tricritical point in a wing-structure phase diagram

Valentin Taufour; Udhara S. Kaluarachchi; Vladimir G. Kogan

doi:10.1103/physrevb.94.060410

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arXiv · 1608.04424

Constraints on the merging of the transition lines at the tricritical point in a wing-structure phase diagram

Valentin Taufour·Udhara S. Kaluarachchi·Vladimir G. Kogan

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Abstract

We consider the phase diagram of a ferromagnetic system driven to a quantum phase transition with a tuning parameter $p$. Before being suppressed, the transition becomes of the first order at a tricritical point, from which wings emerge under application of the magnetic field $H$ in the $T$-$p$-$H$ phase diagram. We show that the edge of the wings merge with tangent slopes at the tricritical point.

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Valentin Taufour, Udhara S. Kaluarachchi, Vladimir G. Kogan. 2016-08-15. Constraints on the merging of the transition lines at the tricritical point in a wing-structure phase diagram. https://doi.org/10.1103/physrevb.94.060410

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