Mapping Yu-Shiba-Rusinov States in atomic and molecular impurities

Javier Zaldivar, Carmen Rubio-Verdú, Deungjang Choi, Stefano Trivini, *Nacho Pascual
CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia - San Sebastian, Spain

Magnetism and superconductivity are phenomena that cannot simultaneously exist in the same region of a material. At the atomic scale, magnetic impurities scatter Cooper pairs as a potential with broken time-reversal symmetry, and create bound states inside the superconducting gap, named Yu-Shiba-Rusinov (YSR) states [1]. We investigate the YSR states caused by several atomic and molecular systems, resolving their origin and exploring basic properties of BCS superconductors.

YSR states are localized around magnetic impurities and their amplitude distribution reflects intrinsic properties of the magnetic system and of its interaction with the superconductor. We will present recent results about the spatial distribution of YSR states on the surfaces of two conventional superconductors, Pb(111) and β-Bi2Pd(100) [2,3]. While in the close proximity to the impurity, YSR states may reflect the projected shape of spin polarized orbitals of atomic adsorbate, on the long range, they picture scattering processes in the superconducting bands

[1] B. W. Heinrich, J. I. Pascual, and K. J. Franke, ArXiv 1705.03672 (2017).

[2] D. J. Choi, C. Rubio, J. Bruijckere, M. M. Ugeda, N. Lorente, J. I. Pascual, Nat. Comm. 8, 15175 (2017).

[3] D. Choi, C. García Fernandez, E. Herrera, C. Rubio-Verdu, M. Ugeda, I. Guillamon, H. Suderow, J. I. Pascual and N. Lorente, Phys. Rev. Lett. 120, 167001 (2018).