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arXiv · 2507.11614

Nesting-driven ferromagnetism of itinerant electrons

Ya. I. Rodionov·A. V. Rozhkov·M. E. S. Beck·A. O. Sboychakov·K. I. Kugel·A. L. Rakhmanov
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Abstract

We theoretically investigate a model with electrons and holes whose Fermi surfaces are perfectly nested. The fermions are assumed to be interacting, both with each other and with the lattice. To suppress inhomogeneous states, a sufficiently strong long-range Coulomb repulsion is included into the model. Using the mean field approximation, one can demonstrate that in the absence of doping, the ground state of such a model is insulating and possesses a density-wave order, either SDW, or CDW. Upon doping, a finite ferromagnetic polarization emerges. It is argued that the mechanism driving the ferromagnetism is not of the Stoner type. A phase diagram of the model is constructed, and various properties of the ordered phases, such as half-metallicity and cone magnetic structure, are studied.

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Ya. I. Rodionov, A. V. Rozhkov, M. E. S. Beck, A. O. Sboychakov, K. I. Kugel, A. L. Rakhmanov. 2025-07-15. Nesting-driven ferromagnetism of itinerant electrons. https://doi.org/10.1103/kpdc-9p8m

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