论文标题
Pauli-limit违反无限镍镍超导体的违规行为
Pauli-limit violation in lanthanide infinite-layer nickelate superconductors
论文作者
论文摘要
超导性可以通过磁场破坏,上限在自旋单向超导体中称为Pauli-limit。几乎所有发现的超导体都是旋转的,在铜酸盐家族中达到的环境压力下的过渡温度最高。最近发现的最接近的铜酸盐类似物是最近发现的无限层镍,它具有与铜酸盐的实质性结构和电子相似性。先前对ND $ _ {0.775} $ sr $ _ {0.225} $ nio $ _2 $的磁转运研究已经观察到同性恋Pauli限制的上层关键领域。在这里,我们在每个晶体学方向上报告了大型违反Pauli-limit,无论是掺杂$ x $,la $ _ {1-x} $(ca/sr)$ _ x $ nio $ _2 $。如此大的违反Pauli-limit在LA $ _ {1-X} $(CA/SR)$ _ x $ nio $ _2 $的各个方向上是出乎意料的,并且不可能由Fulde Ferrell-Larkin-Larkin-ovchinnikov(fflo) - State- State,强的Spin-Orbit-Orbit-Orbit-coupling或一个强度csepling或一个大psepspseud。另一方面,与先前的报告一致,我们观察到nd $ _ {1-x} $ sr $ _x $ nio $ _2 $中的Pauli限制关键领域,而超导性各向异性随着兴奋剂的增加而降低,这表明旋转旋转配对。因此,La $ _ {1-x} $(Ca/sr)中的超导能力可以由非旋转singlet Cooper配对机制驱动,具有有吸引力的高$ t_c $ 10 k时,比已知的旋转三胞胎超级负责人的应用程序高于旋转的超级方面的应用,该命令高于10 k,高度高度的序列范围是高度不佳的旋转式超级。 Spintronics和量子计算。
Superconductivity can be destroyed by a magnetic field with an upper bound known as the Pauli-limit in spin-singlet superconductors. Almost all the discovered superconductors are spin-singlet, with the highest transition temperature $T_c$ at ambient pressure achieved in the cuprate family. The closest cuprate analogue is the recently discovered infinite-layer nickelate, which hosts substantial structural and electronic similarity to the cuprate. A previous magnetotransport study on Nd$_{0.775}$Sr$_{0.225}$NiO$_2$ has observed an isotropic Pauli-limited upper critical field. Here, we report a large violation (>2 times) of Pauli-limit in every crystallographic directions in La$_{1-x}$(Ca/Sr)$_x$NiO$_2$ regardless of the doping $x$. Such a large violation of the Pauli-limit in all directions in La$_{1-x}$(Ca/Sr)$_x$NiO$_2$ is unexpected and unlikely accounted by a Fulde Ferrell-Larkin-Ovchinnikov (FFLO)-state, strong spin-orbit-coupling, strong-coupling or a large pseudogap. On the other hand, in agreement with the previous report, we observe a Pauli-limiting critical field in Nd$_{1-x}$Sr$_x$NiO$_2$ and the superconducting anisotropy decreases as doping increases, suggesting a spin-singlet pairing. Therefore, superconductivity in La$_{1-x}$(Ca/Sr)$_x$NiO$_2$ could be driven by a non-spin-singlet Cooper pairing mechanism with an attractive high-$T_c$ at 10 K, an order of magnitude higher than the known spin triplet superconductors, favourably extending the application of spin-triplet superconductivity in topological matter, non-dissipative spintronics, and quantum computing.