Influence of 4f electronic states on the surface states of rare-earth hexaborides

Abstract

We study the surface electronic structure of a series of rare-earth hexaborides using state-of-the-art high resolution photoemission spectroscopy. Experimental results reveal a surface state around 1.8 eV binding energy in all the hexaborides indicating its generic nature in this class of compounds. The surface and bulk electronic structures near the Fermi level, ε_F are almost similar in each of the compounds. This suggests an interesting possibility of fabricating new materials possessing low work function like LaB₆ where the behavior of mobile electrons can be tuned by rare-earth substitutions.