title: Electron holography studies of the charge on dislocations in GaN.
abstract: Off-axis electron holography in a transmission electron microscope is used to examine the charge on threading edge dislocations in n-GaN (0001). It is shown that the crystal inner potential is reduced within 10 nm of the dislocation consistent with a negatively charged core. The results can be explained by a simple unscreened potential due to a core charge of about 4 x 10(7) electrons cm (-1). The origin of this charge is discussed. The application of the method to other types of dislocation is also considered.
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom. d.cherns@bris.ac.uk
authors.forename: D
authors.initials: D
authors.lastname: Cherns
authors.forename: C G
authors.initials: CG
authors.lastname: Jiao