与超导体耦合的交变磁自旋纹理：畴壁自旋三重态超导性和超电流诱导转矩
Altermagnetic spin textures coupled to superconductors: Domain wall spin-triplet superconductivity and supercurrent-induced torques
AI总结：
研究与传统 s 波超导体耦合的交变磁体中库珀对形式，考虑交变磁序参量空间不均匀性，发现超导性受交变磁畴影响，有三重态热点等，还存在超电流与交变磁序的相互作用，为相关研究提供独特机会。
AI中文摘要：
由于缺乏可观的杂散场以及最近发现的交变磁纹理对巡游电子的高度非平凡影响，我们研究了与传统 s 波超导体耦合的空间变化交变磁体中库珀对的形式。交变磁性对自旋单重态配对的有害影响以及磁序参量纹理导致的局部对称性降低，使得超导性主要影响交变磁畴之间的区域。以平面径向畴壁为例，我们表明出现的塞曼场和自旋轨道场会产生空间分离的三重态热点以及节点和完全能隙超导区域之间的转变，其结构由畴壁和交变磁序参量共同决定。我们还发现了一种相互作用，即超电流会产生继承交变磁序对称性的准粒子介导的四极转矩。我们的结果表明，考虑交变磁序参量的空间不均匀性对于理解超导邻近效应至关重要，并表明交变磁纹理和超导体的混合系统为库珀对的局部工程设计和检测交变磁序提供了独特机会。
英文摘要：
Motivated by the absence of sizable stray fields and the recently discovered highly non-trivial impact of altermagnetic textures on itinerant electrons, we here study the form of Cooper pairs in spatially varying altermagnets coupled to conventional $s$-wave superconductors. As a consequence of the detrimental impact of altermagnetism on spin-singlet pairing and the local symmetry reduction caused by textures in the magnetic order parameter, we show that superconductivity predominantly impacts the regions between altermagnetic domains. Focusing on a planar radial domain wall for concreteness, we show that emergent Zeeman and spin-orbit fields create spatially separated triplet hotspots and transitions between nodal and fully gapped superconducting regions, whose structure is set by both the domain wall and the altermagnetic order parameter. We also identify a reciprocal effect, where a supercurrent generates a quasiparticle-mediated quadrupolar torque that inherits the symmetry of the altermagnetic order. Our results show that accounting for spatial inhomogeneities in the altermagnetic order parameter is essential for an understanding of the superconducting proximity effect and suggest that hybrid systems of altermagnetic textures and superconductors offer unique opportunities for local engineering of Cooper pairs and for detecting altermagnetic order.
