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arXiv · 1708.00103

Quantum triple point and quantum critical endpoints in metallic magnets

D. Belitz·T. R. Kirkpatrick
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Abstract

In low-temperature metallic magnets, ferromagnetic (FM) and antiferromagnetic (AFM) orders can exist in a single system in different parts of the phase diagram as a function of some control parameter. These phases can be adjacent, or exist concurrently, resulting in a phase transition between a FM phase and an AFM one, or between a phase of concurrent FM and AFM order and either of the pure phases. We show that universal quantum fluctuations qualitatively alter the known phase diagrams for classical magnets: They shrink the region of concurrent FM and AFM order, change various transitions from second to first order, and, in the presence of a magnetic field, lead to either a quantum triple point where the FM, AFM and paramagnetic phases coexist, or to a quantum critical end point.

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D. Belitz, T. R. Kirkpatrick. 2017-08-06. Quantum triple point and quantum critical endpoints in metallic magnets. https://doi.org/10.1103/physrevlett.119.267202

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