Probing non-dipole allowed excitations in highly correlated materials with nanoscale resolution
Journal
Ultramicroscopy
Journal Volume
109
Journal Issue
11
Pages
1333-1337
Date Issued
2009
Author(s)
Abstract
Here, we demonstrate that non-dipole allowed d-d excitations in NiO can be measured by electron energy loss spectroscopy (EELS) in transmission electron microscopes (TEM). Strong excitations from (3)A(2g) ground states to (3)T(1g) excited states are measured at 1.7 and 3 eV when transferred momentum are beyond 1.5 A(-1). We show that these d-d excitations can be collected with a nanometrical resolution in a dedicated scanning transmission electron microscope (STEM) by setting a good compromise between the convergence angle of the electron probe and the collected transferred momentum. This work opens new possibilities for the study of strongly correlated materials on a nanoscale.
SDGs
Type
journal article