Quasi-one dimensional electronic state of alkali metal chains assembled on the InAs(110) surface

We investigate the electronic band dispersion associated to alkali metal chains assembled on the InAs(110) surface by angular-resolved photoelectron spectroscopy. The Cs and K atomic chains induce occupied electronic states with twofold symmetry and narrow bandwidth along the chain direction, showing a quasi-one-dimensional electronic character. The insulating character and the narrow bandwidth of the alkali-induced state suggest the relevance of electron correlation effects in the description of alkali-induced electronic-state dispersion.