Altermagnetic Schottky Contact

Yee Sin Ang

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arXiv · 2310.11289

Altermagnetic Schottky Contact

Yee Sin Ang

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Abstract

Altermagnet is an emerging antiferromagnetic material subclass that exhibits spin-splitting in momentum space without net global magnetization and spin-orbit-coupling effect. In this work, we develop a model of thermal charge injection across an altermagnet/semiconductor (AM/S) Schottky contact. We obtain analytical expressions describing the spin-dependent thermionic current injection across the AM/S contact under any arbitrary interface orientation angles. Interestingly, the spin-contrasting Fermi surface of an altermagnetic electrode enables spin-polarized current to be injected into a nonmagnetic semiconductor even though the system has net-zero magnetization. Our findings thus reveal an altermagntic mechanism to achieve spin injection without involving ferromagnetic ordering. The AM/S Schottky contact proposed here shall provide a potential altermagnetic building block of spintronic devices that are resilient against stray magnetic field perturbation and inherently compatible with ultracompact integration.

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Yee Sin Ang. 2023-10-17. Altermagnetic Schottky Contact. https://arxiv.org/abs/2310.11289

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