2nd CHIRALTEM workshop

3rd CHIRALTEM workshop

NEW: get together at DPG conference


- Vienna - Regensburg -

-Dresden - Prag - Triest -





The Story

Circular dichroism measures the chirality of electronic transitions. You need a circularly polarized beam of photons to do it.

Would it be possible to use electrons instead of photons? The commonsense answer is: Yes, but you need spin polarized electrons:

We say: Yes, but you can do it in a regular transmissioen electron microscope. You need no exotic electrons, nor a synchrotron.

No one tried it before. So we decided to do it. It will not be an easy task.

What is it good for?

The general objective of CHIRALTEM is to prove that circular dichroism can be observed in the transmission electron microscope (TEM) by a novel technique, and thus open a completely new path for studying and characterising magnetic materials. The expected results of the project are a) the experimental verification of a predicted phenomenon in electron scattering; and b) establishing a new method for the characterization of materials, thus pushing European technology in the growing field of spintronics. It will complement the XMCD applications at synchrotrons and provide new insights for physics and materials science.

Measurement principle

The idea is to measure the mixed dynamic form factor (MDFF) of a chiral electronic transition. Under particular conditions (violation of time reversal symmetry) the MDFF shows asymmetry with respect to handedness.