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arXiv · 2606.13395

Andreev Reflection to Probe Momentum-Dependent Spin Polarization in Altermagnet CrSb

Yan Zhang·Yixuan Luo·Yue Yang·Zilong Li·Weilong Qiu·Lunhui Hu·Yuanfeng Xu·Yanfeng Guo·Chao Cao·Xin Lu
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Abstract

Altermagnetic materials have recently emerged as promising candidates for next-generation spintronic applications, characterized by the k-dependent spin-splitted band structure and a simultaneous zero-net-magnetization. Among them, altermagnetic candidate CrSb has attracted considerable attention, owing to its g-wave spin splitting and high Néel temperature. In this article, we employed mechanical point-contact spectroscopy (MPCS) with superconducting Nb tips to probe the Andreev reflection on CrSb single crystals along three principal crystallographic orientations. The extracted momentum-dependent spin polarizations are approximately 73.4% for the (0001) plane, 67.9% for the (-1-120) plane, and 61.9% for the (10-10) plane, respectively, distinct from conventional antiferromagnets. Furthermore, conductance spectra from spatial line-scans on the sample surface support the existence of altermagnetic domains with a characteristic size of 250-500 nm separated by domain-walls with width about 250 nm. These results strongly support the momentum-dependent spin polarization in altermagnetic CrSb and establish Andreev reflection as a new paradigm to probe k-dependent spin textures.

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Yan Zhang, Yixuan Luo, Yue Yang, Zilong Li, Weilong Qiu, Lunhui Hu, Yuanfeng Xu, Yanfeng Guo, Chao Cao, Xin Lu. 2026-06-11. Andreev Reflection to Probe Momentum-Dependent Spin Polarization in Altermagnet CrSb. https://doi.org/10.1103/42m7-p7l3

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