论文标题
$ sr_2ruo_4 $的超导子类和大量骑士移动
Superconducting subphase and substantial Knight shift in $Sr_2RuO_4$
论文作者
论文摘要
最近测量$ SR_2RUO_4 $骑士转移的核磁共振实验挑战了该超导体中的手性配对的图像。在这里，我们研究了螺旋配对对超导状态的含义，同时将我们的结果与上临界场和骑士移动的可用实验数据进行了比较。我们采用现实的三维紧密结合模型来解决Bogoliubov-De-Gennes方程，该模型很好地捕获了实验性费米表面。与实验一致，我们发现Pauli限制了上部临界场，并且在低温和高场，第二个超导过渡。这些在H-T相图中形成超导子相的过渡本质上是一阶，并在双智度点$（T^\ ast，h^\ ast $）下合并为单一的二阶过渡，我们发现（0.8〜K，2.4〜T）与实验报告（0.8〜K，2.4〜T）（0.8〜K，$ \ sim $ sim $ 1.2〜t） Rev. B} \ TextBf {93}，184513（2016）]。此外，我们发现骑士转移与最近的实验一致。
Recent nuclear magnetic resonance experiments measuring the Knight shift in $Sr_2RuO_4$ have challenged the widely accepted picture of chiral pairing in this superconductor. Here we study the implications of helical pairing on the superconducting state while comparing our results with the available experimental data on the upper critical field and Knight shift. We solve the Bogoliubov-de-Gennes equation employing a realistic three-dimensional tight-binding model that captures the experimental Fermi surface very well. In agreement with experiments we find a Pauli limiting to the upper critical field and, at low temperatures and high fields, a second superconducting transition. These transitions which form a superconducting subphase in the H-T phase diagram are first-order in nature and merge into a single second-order transition at a bicritical point $(T^\ast,H^\ast$), for which we find (0.8~K, 2.4~T) with experiment reporting (0.8~K, $\sim$ 1.2~T) [\textit{Phys. Rev. B} \textbf{93}, 184513 (2016)]. Furthermore, we find a substantial drop in the Knight shift in agreement with recent experiments.
