Synchrotron radiation photoemission study of the electronic structure of the filled tetrahedral semiconductors LiZnAs and LiZnP

Abstract

Ultraviolet photoemission utilizing synchrotron radiation has been used to characterize the electronic band structure of the Nowotny-Juza A IB IIC v type interstitially filled tetrahedral semiconductors LiZnAs and LiZnP. This is the first photoemission investigation performed on these materials. The LiZnAs and LiZnP crystals were grown by direct fusion of the constituent elements and are p-type semiconductors with direct optical band gaps of 1.25 eV and 2.1 eV, respectively. The experimentally observed Zn 3d binding energies with respect to the valence band maximum for these materials are compared with the photoemission results for various II–V and II–VI Zn compounds in order to qualify the relative ionicity as well as the proposed p-d repulsion and hybridization effects. The results are further compared with the theorectically predicted band structure of LiZnAs and LiZnP calculated using self-consistent first principles theory and physically interpreted by an interstitial insertion rule.