Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1.
Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
Nat Commun. 2017 Jun 29;8:15996. doi: 10.1038/ncomms15996.
Spin fluctuations are a leading candidate for the pairing mechanism in high temperature superconductors, supported by the common appearance of a distinct resonance in the spin susceptibility across the cuprates, iron-based superconductors and many heavy fermion materials. The information we have about the spin resonance comes almost exclusively from neutron scattering. Here we demonstrate that by using low-temperature scanning tunnelling microscopy and spectroscopy we can characterize the spin resonance in real space. We show that inelastic tunnelling leads to the characteristic dip-hump feature seen in tunnelling spectra in high temperature superconductors and that this feature arises from excitations of the spin fluctuations. Spatial mapping of this feature near defects allows us to probe non-local properties of the spin susceptibility and to image its real space structure.
自旋涨落是高温超导体配对机制的主要候选者，这一观点得到了在铜氧化物、铁基超导体和许多重费米子材料中自旋磁化率中普遍存在的独特共振的支持。我们关于自旋共振的信息几乎完全来自于中子散射。在这里，我们证明通过使用低温扫描隧道显微镜和光谱学，我们可以在实空间中对自旋共振进行表征。我们表明，非弹性隧道导致了在高温超导体的隧道光谱中看到的特征的凹陷-峰特征，并且该特征源自于自旋涨落的激发。在缺陷附近对该特征进行空间映射，使我们能够探测自旋磁化率的非局域性质，并对其实空间结构进行成像。
