论文标题
单轴菌株，拓扑带奇异性和超导体的配对对称性变化
Uniaxial strain, topological band singularities and pairing symmetry changes in superconductors
论文作者
论文摘要
单轴菌株通过改变晶格对称性以及改变费米表面拓扑来影响超导体中的对称态。在这里，我们在S，P和D-Wave配对状态的一波段负-U哈伯德模型中介绍了这些效应的系统研究。我们考虑了一个通用的2D模型，该模型可以应用于单轴菌株下的超导体，该模型是通过在方形晶格上跳高各向异性建模的。此处介绍的结果A沿X轴的平面压缩模型，从而将晶格对称性从四方将晶格对称性降低到正交晶体空间群。探索了各向异性对不同类型的间隙配对的影响。我们表明，TC的变化可通过跳跃各向异性来调整，并取决于与在Lifshitz过渡过程中Fermi表面的开放有关的间隙函数的方向。在将模型结果与SR2RUO4情况下的实验数据进行比较时，发现D + ID和D + IG配对都可以最好地描述超导状态的TC的变化，这些变化在其对小单轴菌株的响应方面。
Uniaxial strain affects pairing symmetry states in superconductors by changing the lattice symmetry, and by altering Fermi surface topology. Here, we present a systematic study of these effects within a one-band negative-U Hubbard model for s, p and d-wave pairing states. We consider a general 2D model that can be applied to superconductors under uniaxial strain, modelled via hopping anisotropy, on a square lattice. The results presented here model an in plane compression along the x-axis, which reduces the lattice symmetry from a tetragonal to an orthorhombic crystal space group. The effects of hopping anisotropy on the different types of gap pairings are explored. We show that changes in Tc are tunable with hopping anisotropy and depend on the orientation of the gap function in relation to the opening of the Fermi surface during the Lifshitz transition. In comparing the model results to experimental data for the case of Sr2RuO4 it is found that both the d + id and d + ig pairings best describe the changes in Tc for the superconducting state in regards to its response to small uniaxial strain.
