Uniaxial spin texture in a superconducting electron gas revealed by exchange interactions

Junyi Yang; Changjiang Liu; Xianjing Zhou; Hanyu Hou; Kaijun Yin; Jianguo Wen; John Pearson; Alexey Suslov; Dafei Jin; Jidong S. Jiang; Ulrich Welp; Jian-Min Zuo; Michael R. Norman; Anand Bhattacharya

doi:10.1126/sciadv.aeb1601

arXiv · 2502.19599

Uniaxial spin texture in a superconducting electron gas revealed by exchange interactions

Junyi Yang·Changjiang Liu·Xianjing Zhou·Hanyu Hou·Kaijun Yin·Jianguo Wen·John Pearson·Alexey Suslov·Dafei Jin·Jidong S. Jiang·Ulrich Welp·Jian-Min Zuo·Michael R. Norman·Anand Bhattacharya

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Abstract

Two-dimensional superconductors with spin-textured Fermi surfaces can be a platform for realizing unconventional pairing states and are of substantial interest in the context of quantum information science, and superconducting spintronics/orbitronics. We observed an unusual in-plane uniaxial anisotropy in the superconducting 2D electron gas (2DEG) formed at EuOx/KTaO3 (110) interfaces, where the EuOx is magnetic. This anisotropy is not evident in AlOx/KTaO3 (110) where the overlayer is non-magnetic. Our results are consistent with a highly anisotropic 'half-Rashba' spin-textured Fermi surface in 2DEGs formed at the KTaO3 (110) interface that is hidden from external magnetic fields due to a near cancellation between orbital and spin moments but revealed by exchange interactions of the electrons in the 2DEG with Eu moments near the EuOx/KTaO3 (110) interface. The interactions between the uniaxial spin texture and the magnetic overlayer offer new ways to explore the interplay between magnetism and 2D superconductivity.

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cond-mat.supr-con cond-mat.mes-hall cond-mat.mtrl-sci

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Junyi Yang, Changjiang Liu, Xianjing Zhou, Hanyu Hou, Kaijun Yin, Jianguo Wen, John Pearson, Alexey Suslov, Dafei Jin, Jidong S. Jiang, Ulrich Welp, Jian-Min Zuo, Michael R. Norman, Anand Bhattacharya. 2025-02-26. Uniaxial spin texture in a superconducting electron gas revealed by exchange interactions. https://doi.org/10.1126/sciadv.aeb1601

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