Circular Dichroism in the TEM and in the Synchrotron

Dichroism is the polarisation dependency of the fine structure in X-ray absorption spectra (XANES). The similarities between XANES and energy loss near edge structures (ELNES) in the Transmission Electron Microscope (TEM) have long been recognised, and attempts to measure linear dichroism to the TEM were successful. A similar task for circular dichroism was considered to be impossible with present technology. To everyone's surprise, magnetic circular dichroism has been observed recently in a TEM equipped with an energy filter (1) . In the following we compare the dichroic signals obtained on a TECNAI F20 field emission microscope with the one from the ELETTRA synchrotron, both obtained from the same Fe specimen.