The Haldane model under uniaxial strain

The topological features of Haldane model under strain are studied using a tight-binding approach. Strain induces a time-reversal preserving pseudo-magnetic field that quantizes the bulk states inducing pseudo Landau levels. Unlike the time-reversal symmetry breaking induced by a real magnetic field, strain lifts the degeneracy of the zero-energy Landau level in each valley. The degeneracy is also lifted in the presence of a potential that breaks the sublattice inversion symmetry. In addition, strain also modifies locally the Fermi velocity and induces a tilt of the Landau levels.