Physical Review X (Jan 2019)
p-Band Engineering in Artificial Electronic Lattices
Abstract
Artificial electronic lattices, created atom by atom in a scanning tunneling microscope, have emerged as a highly tunable platform to realize and characterize the lowest-energy bands of novel lattice geometries. Here, we show that artificial electronic lattices can be tailored to exhibit higher-energy bands. We study p-like bands in fourfold and threefold rotationally symmetric lattices. In addition, we show how an anisotropic design can be used to lift the degeneracy between p_{x}- and p_{y}-like bands. The experimental measurements are corroborated by muffin-tin and tight-binding calculations. The approach to engineer higher-energy electronic bands in artificial quantum systems introduced here enables the realization of complex band structures from the bottom up.