Presentation Information
[1P20]STM/S Study on Si (111) - √7×√3 Pb
*WEN SI1, Junya Okazaki1, Masahiro Haze1, Yukio Hasegawa1 (1. The Institute for Solid State Physics, the University of Tokyo)
This study examines the effects of dimensionality and disorder on superconductivity, particularly in monolayer Pb on Si (111). While bulk superconductivity is resilient to non-magnetic disorders, it becomes fragile in two-dimensional systems. The Si (111)-Pb striped-incommensurate (SIC) phase shows robust superconducting properties despite disorders, whereas the more diluted Si (111) – √7×√3 Pb (1.2 ML) phase displays increased sensitivity, functioning similarly to Josephson junctions. Previous research using scanning tunneling potentiometry identified distinct potential drops across the steps and indicating differing superconducting coherence between these phases. Our latest low-temperature scanning tunneling microscopy/spectroscopy (STM/STS) experiments further explore vortex behavior in the √7×√3 phase, providing topographic images, STS spectra, and zero-bias conductance mapping, which illustrate the spatial distribution of vortices and highlight the differences from the SIC phase.