Spontaneous Fully Compensated Ferrimagnetism

Bingbing Wang; Yongpan Li; Yichen Liu; Cheng-Cheng Liu

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arXiv · 2602.24135

Spontaneous Fully Compensated Ferrimagnetism

Bingbing Wang·Yongpan Li·Yichen Liu·Cheng-Cheng Liu

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Abstract

We propose a general mechanism for the spontaneous emergence of filling-enforced fully compensated ferrimagnetism (fFIM), characterized by zero net magnetization yet ferromagnetic-like spin-split band structures. Using Hartree-Fock mean-field calculations of the Hubbard model, we map out the stability regime of spontaneous fFIM over a broad parameter space of interaction strength and staggered potential. We show the unique quantum-geometry-governed optical selection rules and the abundant valley- and spin-related physics of electronics and optics arising from the emergence of fFIM order, with tunable spin-polarized and valley-contrasting charge and spin currents. Furthermore, based on our theory, we demonstrate that spontaneous fFIM can be realized in nominally nonmagnetic graphene via defect engineering. Our results establish a unified framework for the mechanism, emergent properties, and materials realization of spontaneous fFIM, opening new opportunities for spintronic, valleytronic, and optoelectronic applications.

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Bingbing Wang, Yongpan Li, Yichen Liu, Cheng-Cheng Liu. 2026-02-27. Spontaneous Fully Compensated Ferrimagnetism. https://arxiv.org/abs/2602.24135

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