Josephson Vortex in Indium Monatomic Superconductor on Silicon Terraces

Superconductivity in Indium monatomic layer on a surface of Silicon substrate is intriguing where the terraces and steps exist. Recently, elliptic vortices trapped at steps have been observed by STM/STS measurement under magnetic field [1]. Motivated by this experiment, we clarify the quasiparticle excitation by using Bogoliubov-de Gennes approach [2]. The current distribution and zero energy density of states at vortex core show elliptic shape with longer axis parallel to the step. Moreover, the order parameter is restored at the vortex core. By comparing theoretical results with experiments, we conclude that the recent STS measurement has directly detected Josephson vortex. [1] S. Yoshizawa, {\it et al}., {\it Phys. Rev. Lett.} (in press, arXiv:1405.5953). [2] T. Kawakami, {\it et al}., {\it J. Phys.: Conf. Ser.} (in press).