Band structures of strained kagome lattices

Abstract

Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands. We theoretically investigate the evolution of electronic band structures of kagome lattices in response to uniaxial strain using both a tight-binding model and an antidot model based on a periodic muffin-tin potential. It is found that the Dirac points move with applied strain. Furthermore, the flat band of unstrained kagome lattices is found to develop into a highly anisotropic shape under a stretching strain along y direction, forming a partially flat band with a region dispersionless along ky direction while dispersive along kx direction. Our results shed light on the possibility of engineering the electronic band structures of kagome materials by mechanical strain.