Band Structure in the Excitation Spectrum of Type II Superconductors

The periodic structure of the mixed state leads to some band splitting in rough analogy to the electrons in a metal. The density of states for tunneling perpendicular to the flux lines shows an appreciable depression at energies ħω ≈ (ħ2/2m) kF|l|, l being a reciprocal lattice vector of the flux lattice normal to the tunneling surface.