Determination of mean inner potential of germanium using off-axis electron holography.
Off-axis electron holography has been used to determine the mean inner potential of germanium using cleaved 90 degrees wedge samples, where the wedge thickness profiles were checked by weak-beam dark-field extinction fringes. Dynamical contributions to the phase of the image were minimized by tilting to weakly diffracting conditions, as confirmed by reference to convergent-beam electron diffraction patterns. Small residual corrections were determined using multislice calculations. From a total of 18 separate measurements, it is concluded that the value of the mean inner potential is 14.3(2) V, which agrees with recent theoretical calculations to within experimental error.
Li
J
Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1504, USA. jing.li@asu.edu
McCartney
MR
Dunin-Borkowski
RE
Smith
DJ