Electronic structure of GaN studied with electron energy loss spectroscopy and density functional theory

Department of Materials Science and Metallurgy, University of Cambridge, Pembroke St. Cambridge, CB2 3QZ, UK. * Department of Materials, University of Leeds, Leeds LS2 9JT, UK.

ABSTRACT: The Electron Energy Loss Near -Edge Structure (ELNES) is related to a site-and symmetry-projected, unoccupied density of states (DOS). Therefore, it contains information about the electronic structure and interatomic bonding of materials. In this work, GaN, an important light-emitting semiconductor, is studied. Experimental spectra are compared to theoretical spectra, based on a calculation of the DOS, and excellent agreement is observed when the effects of the core-hole are included. The anisotropy of the electronic structure is also investigated and a discussion of the nature of the bonding in GaN is given.