TY - JOUR
T1 - Mapping the orbital structure of impurity bound states in a superconductor
AU - Choi, Deung Jang
AU - Rubio-Verdú, Carmen
AU - De Bruijckere, Joeri
AU - Ugeda, Miguel M.
AU - Lorente, Nicolás
AU - Pascual, Jose Ignacio
PY - 2017
Y1 - 2017
N2 - A magnetic atom inside a superconductor locally distorts superconductivity. It scatters Cooper pairs as a potential with broken time-reversal symmetry, leading to localized bound states with subgap excitation energies, named Shiba states. Most conventional approaches regarding Shiba states treat magnetic impurities as point scatterers with isotropic exchange interaction. Here, we show that the number and the shape of Shiba states are correlated to the spin-polarized atomic orbitals of the impurity, hybridized with the superconductor. Using scanning tunnelling spectroscopy, we spatially map the five Shiba excitations found on subsurface chromium atoms in Pb(111), resolving their particle and hole components. While particle components resemble d orbitals of embedded Cr atoms, hole components differ strongly from them. Density functional theory simulations correlate the orbital shapes to the magnetic ground state of the atom, and identify scattering channels and interactions, all valuable tools for designing atomic-scale superconducting devices.
AB - A magnetic atom inside a superconductor locally distorts superconductivity. It scatters Cooper pairs as a potential with broken time-reversal symmetry, leading to localized bound states with subgap excitation energies, named Shiba states. Most conventional approaches regarding Shiba states treat magnetic impurities as point scatterers with isotropic exchange interaction. Here, we show that the number and the shape of Shiba states are correlated to the spin-polarized atomic orbitals of the impurity, hybridized with the superconductor. Using scanning tunnelling spectroscopy, we spatially map the five Shiba excitations found on subsurface chromium atoms in Pb(111), resolving their particle and hole components. While particle components resemble d orbitals of embedded Cr atoms, hole components differ strongly from them. Density functional theory simulations correlate the orbital shapes to the magnetic ground state of the atom, and identify scattering channels and interactions, all valuable tools for designing atomic-scale superconducting devices.
UR - http://resolver.tudelft.nl/uuid:0191bbf1-3058-4fba-be31-6ba5473a4c74
UR - http://www.scopus.com/inward/record.url?scp=85018880973&partnerID=8YFLogxK
U2 - 10.1038/ncomms15175
DO - 10.1038/ncomms15175
M3 - Article
AN - SCOPUS:85018880973
SN - 2041-1723
VL - 8
JO - Nature Communications
JF - Nature Communications
M1 - 15175
ER -