Checkerboard density of states in strong-coupling superconductors

The Bogoliubov-de Gennes (BdG) equations are solved in the strong-coupling limit, where real-space (preformed) pairs bose-condense with finite center-of-mass momenta. There are two energy scales in this regime, a temperature independent incoherent gap $\Delta_p$ and a temperature dependent coherent gap $\Delta_c (T)$, modulated in real space. The single-particle density of states (DOS) reveals checkerboard modulations similar to the tunnelling DOS in cuprates.