Field-induced gap, pseudogap and new Van Hove singularity in the triangular lattice

We investigate the energy spectrum and the density of states (DOS) in a 2D triangular tight-binding model with hopping integrals modulated by staggered magnetic fluxes (SMFs). Three different types of SMFs are considered. The SMFs result in shifts of the original Van Hove singularity (VHS) peak in the DOS, or even generate new flux-dependent VHSs. And a gap or a pseudogap can also be generated on the original Fermi surface. The magnitude of the pseudogap or the gap and its symmetries depend on the chemical potential μ, and on the flux parameters.