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arXiv · 2506.22770

Strain-Induced Non-alter Compensated Magnet and Its Application to Magnetic Tunnel Junction Device Design

Abstract

The recent proposal of altermagnetism has drawn widespread attention to antiferromagnet (AFM) exhibiting spin splitting, extending beyond the realm of sign-alternating spin splitting in momentum space protected solely by rotational symmetry. Herrin, we propose a shear-strain strategy that enables significant modulation of d-wave altermagnets into an non-alter compensated magnets. A comprehensive analysis combining the magnetic moment compensation characteristics of opposite spin sublattices with the distribution of spin-resolved conduction channels in momentum space under the [001] crystal orientation reveals that shear strain breaks the rotational symmetry of alternatmagnets. To explore the application potential of non-alter compensated magnets, we designe RuO2/TiO2/RuO2 magnetic tunnel junctions (MTJ) with three crystallographic orientations ((001), (110), (100)) and investigated their transport properties under shear strain. This non-alter electronic structure not only enhances the tunneling magnetoresistance (TMR) in spin-split paths of intrinsic RuO2 (226% to 431%) but also enables substantial TMR in spin-degenerate paths (from 0-88%)). Our work provides guidelines for broadening magnetic materials and device platforms.

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Fangqi Liu, Yanrong Song, Zhenhua Zhang, Yong Liu, Sicong Zhu, Zhihong Lu, Rui Xiong. 2025-06-28. Strain-Induced Non-alter Compensated Magnet and Its Application to Magnetic Tunnel Junction Device Design. https://arxiv.org/abs/2506.22770

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