The influence of ripple waves on the band diagram of zigzag strained graphene nanoribbons (GNRs) is analyzed
by utilizing the finite element method. Such waves have their origin in electromechanical effects. With a novel
model, we demonstrate that electron-hole band diagrams of GNRs are highly influenced (i.e. level crossing of the
bands are possible) by two combined effects: pseudo-magnetic fields originating from electroelasticity theory and
external magnetic fields. In particular, we show that the level crossing point can be observed at large external
magnetic fields (B ≈ 100T ) in strained GNRs, when the externally applied tensile edge stress is on the order of
-100 eV/nm and the amplitude of the out-of-plane ripple waves is on the order of 1nm.