Atomic resolution electron energy-loss spectroscopy

Electron energy-loss spectroscopy (EELS) has been successfully used to measure the electronic structure of materials with atomic (i.e. sub-nanometer) spatial resolution. Furthermore, the combination of incoherent Z-contrast imaging and EELS allows us to correlate structural features, such as defects or interfaces directly with the changes in the local electronic structure. In this review, we will discuss the theoretical aspects and experimental procedures for achieving atomic-resolution EELS. In particular, we will describe the practicalities of the combination of Z-contrast imaging and EELS, used in the scanning transmission electron microscopy mode and also describe some of our recent results where column-by-column EELS has helped solve important material science problems.