论文标题
原子层晶体材料中的现场弹性超导性
Field resilient superconductivity in atomic layer crystalline materials
论文作者
论文摘要
最近的一项研究[S. Yoshizawa {\it et al}., Nature Communications {\bf 12}, 1462 (2021)] reported the occurrence of field-resilient superconductivity, that is, enhancement of the in-plane critical magnetic field $H^{||}_{\rm c2}$ beyond the paramagnetic limiting field, in atomic-layer crystalline （$ \ sqrt {7} \ times \ sqrt {3} $） - 在si（111）基质中。本文在这种高度结晶的二维材料中阐明了观察到的野外非中性非对称超导的起源。我们通过将费米表面各向异性与各向异性自旋分裂和特定于原子层晶体系统的纹理结合在一起，从而发展出超导性的准经典理论。在Si（111） - （$ \ sqrt {7} \ times \ sqrt {3} $）中 - 在一种典型的材料中，我们显示了一个示例，我们显示了一个示例，其中ASOC和障碍的组合可以抑制paramagnetic depirt and parmagnetic depairing and $ hanlancmmem，与各向同性系统相比，仅当由于各向异性自旋纹理而沿特定方向应用磁场时，C2} $。我们还研究了平均混合效果，以证明$ h^{||} _ {\ rm c2} $的增强在中等清洁的政权中受到限制，因为在较大的奇数奇怪的奇怪奇数组件中，脆弱的$ s $ s $ s $ s $+$ p $ -wave配对与非磁性散射的情况下。此外，从对过渡线的分析中，我们确定了考虑到顺磁性效应的散射和抑制的现场耐酸因子，并讨论了野外韧性超导性的起源。通过拟合$ h^{||} _ {\ rm c2} $数据，讨论了正常的电子散射，重点是原子步骤在Si（111）表面上的作用。
A recent study [S. Yoshizawa {\it et al}., Nature Communications {\bf 12}, 1462 (2021)] reported the occurrence of field-resilient superconductivity, that is, enhancement of the in-plane critical magnetic field $H^{||}_{\rm c2}$ beyond the paramagnetic limiting field, in atomic-layer crystalline ($\sqrt{7}\times\sqrt{3}$)-In on a Si(111) substrate. The present article elucidates the origin of the observed field-resilient noncentrosymmetric superconductivity in this highly crystalline two-dimensional material. We develop the quasiclassical theory of superconductivity by incorporating the Fermi surface anisotropy together with an anisotropic spin splitting and texture specific to atomic-layer crystalline systems. In Si(111)-($\sqrt{7}\times\sqrt{3}$)-In, a typical material with a large antisymmetric spin-orbit coupling (ASOC), we show an example where the combination of the ASOC and disorder effect suppresses the paramagnetic depairing and can lead to an enhancement of $H^{||}_{\rm c2}$ compared to an isotropic system only when a magnetic field is applied in a particular direction due to an anisotropic spin texture. We also study the parity-mixing effect to demonstrate that the enhancement of $H^{||}_{\rm c2}$ is limited in the moderately clean regime because of the fragile $s$+$p$-wave pairing against nonmagnetic scattering in the case of the dominant odd-parity component of a pair wavefunction. Furthermore, from analysis of the transition line, we identify the field-resilience factor taking account of the scattering and suppression of paramagnetic effects and discuss the origin of the field-resilient superconductivity. Through fitting of the $H^{||}_{\rm c2}$ data, the normal-state electron scattering is discussed with a prime focus on the role of atomic steps on a Si(111) surface.
