Figure 4: Fe adatoms on Pb (111) surface.
From: Two-dimensional chiral topological superconductivity in Shiba lattices
Electronic structure obtained from density-functional-theory (DFT) calculations. (a) The atomic configuration: Fe adatoms form a buckled a honeycomb lattice on the Pb (111) surface. (b) Fermi surface of the Fe d-orbitals at energy EF=0.09 eV, where the Wigner–Seitz cell (dashed line) and the primitive vectors (arrowed lines) for the reciprocal lattice are indicated. A single Fermi surface is found around the Γ point in this case. (c) DFT band structure of the Fe d-orbitals with spin-orbit coupling. (d) Chern number of the Bogoliubov-de Gennes bands, as a function of Fermi energy, when s-wave superconductivity (Δ=0.01 eV in this calculation) is introduced in the system. The green dashed lines in both (c) and (d) mark the same energy corresponding to the Fermi surface given in (b).
