Capturing the Dynamics of Antiferromagnetic Ordering with Ultrafast Electron Diffraction

Martin Centurion (Physics)

This project aims at exploring ultrafast changes in magnetic properties of materials on the nanometer and sub-nanometer scale, using ultrafast electron diffraction (UED).  The project focuses on investigating the antiferromagnetic phase transition in Chromium, but could be extended to other magnetic materials if the initial set of experiments is successful. The new capabilities are important for exploring the switching properties of materials, and to develop a fundamental understanding of magnetic ordering phase transitions.

We are planning to explore the antiferromagnetic phase transition by impulsively heating the materials with a femtosecond laser pulse and capturing the magnetic order with UED as the antiferromagnetism disappears above the transition temperature, and then as the magnetic order reappears as the sample cools down. The unique ability to probe samples at the sub-Angstrom level with the femtosecond resolution of UED brings a new dimension which is currently not available in the MRSEC.