Anisotropic vortices on superconducting Nb(110)

  title={Anisotropic vortices on superconducting Nb(110)},
  author={Artem Odobesko and Felix Friedrich and Song-Bo Zhang and Soumyajyoti Haldar and Stefan Heinze and Bjorn Trauzettel and Matthias Bode},
  journal={Physical Review B},
We investigate the electronic properties of type-II superconducting Nb(110) in an external magnetic field. Scanning tunneling spectroscopy reveals a complex vortex shape which develops from circular via coffee bean-shaped to elliptical when decreasing the energy from the edge of the superconducting gap to the Fermi level. This anisotropy is traced back to the local density of states of Caroli-de-Gennes-Matricon states which exhibits a direction-dependent splitting. Oxidizing the Nb(110) surface… 

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