论文标题
双杂质式准粒子干扰的双曲线边缘信号
Hyperbolic fringe signal for twin impurity quasiparticle interference
论文作者
论文摘要
我们研究了从间隙超导体（SC）表面上的一对相邻杂质发出的准粒子干扰（QPI）模式。我们发现，QPI信号中的双曲条纹（HF）可能会出现，这是由于两种障碍散射的循环贡献，其中两个杂质的位置是双曲线重点点。对于单个袋式费米学，HF模式信号是非磁杂质的手性SC顺序，并且需要非手续SC的磁性杂质。对于多口袋方案，签名订单参数，例如$ s _ {\ pm} $ - wave同样会产生HF签名。我们讨论了双杂质QPI，作为补充局部光谱分析分析的新工具。
We study the quasiparticle interference (QPI) pattern emanating from a pair of adjacent impurities on the surface of a gapped superconductor (SC). We find that hyperbolic fringes (HF) in the QPI signal can appear due to the loop contribution of the two-impurity scattering, where the location of the two impurities are the hyperbolic focus points. For a single pocket Fermiology, an HF pattern signals chiral SC order for non-magnetic impurities and requires magnetic impurities for non-chiral SC. For a multi-pocket scenario, a sign-changing order parameter such as $s_{\pm}$-wave likewise yields an HF signature. We discuss twin impurity QPI as a new tool to complement the analysis of superconducting order from local spectroscopy.
