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arXiv · 1906.09605

Quantum Ferromagnetic Transition in Clean Dirac Metals

T. R. Kirkpatrick·D. Belitz
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Abstract

The ferromagnetic quantum phase transition in clean metals with a negligible spin-orbit interaction is known to be first order due to a coupling of the magnetization to soft fermionic particle-hole excitations. A spin-orbit interaction gives these excitations a mass, suggesting the existence of a ferromagnetic quantum critical point in metals with a strong spin-orbit interaction. We show that this expectation is not borne out in a large class of materials with a Dirac spectrum, since the chirality degree of freedom leads to new soft modes that again render the transition first order.

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T. R. Kirkpatrick, D. Belitz. 2019-06-23. Quantum Ferromagnetic Transition in Clean Dirac Metals. https://doi.org/10.1209/0295-5075/127/57003

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