The Effect on Electron Scattering and Superconductivity Caused by the Honeycomb Superstructure Nickel on Pb(111)

Yen-Hui Lin^1*, Chia-Ju Chen¹, Ta-Yu Yeh¹, Tzu-Hsuan Lin¹, Nitin Kumar¹, Shih-Tang Huang¹, Deng-Sung Lin¹, Gustav Bihlmayer², Pin-Jui Hsu¹

¹Department of Physics, National Tsing Hua University, Hisnchu, Taiwan
²Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, Jülich, Germany

* Presenter:Yen-Hui Lin, email:s105022805@m105.nthu.edu.tw

We investigate the effect of surface electron scattering and superconductivity resulted from the honeycomb superstructure of Ni on Pb(111) by scanning tunneling microscopy/spectroscopy. According to the STM atomic resolution image, the edges of the honeycomb superstructure are bearded edges. From the results of first principle calculation, the dark and bright edge are the fcc-site-terminated and hcp-site-terminated, respectively. The results of spatial QPI mapping show the backscattering events of surface electron on Pb(111) only happen at the fcc-site-terminated edge. By measuring the dI/dU curve along a line crossing the edge, we observe that the superconducting gap at honeycomb superstructure of Ni is slightly larger than that at Pb(111) surface.

Keywords: Asymmetric Electron Scattering, Scanning Tunneling Spectroscopy, Honeycomb, Ni/Pb(111), Superconductivity