Magnetic spectroscopy at high pressures using X-ray magnetic circular dichroism

Abstract

The imbalance in the electronic density of states between spin-up and spin-down electrons characteristic of ferro(ferri)-magnetic materials gives rise to X-ray magnetic circular dichroism (XMCD) in the absorption of circularly polarized X-rays with opposite helicity. These dichroic effects are largest near element-selective atomic resonances and can be used to probe ferro(ferri)-magnetic ordering with element- and electronic orbital-selectivity. We describe recent developments at the Advanced Photon Source that allow measurements of XMCD in a diamond anvil cell. We discuss the challenges associated with these measurements as well as their potential to further our understanding of complex magnetic materials.

Keywords:

• magnetism
• X-ray magnetic circular dichroism
• XMCD
• synchrotron radiation
• X-ray absorption

Acknowledgements

Work at Argonne and Ames is supported by the US Department of Energy, Office of Science, under Contract Nos. DE-AC-02-06CH11357 and DE-AC02-07CH11358, respectively. The authors would like to thank Dr A.O. Tsokol for providing some of the samples, and Drs Valentin Iota and Yang Ding for helpful discussions.

This material is published by permission of the Argonne National Laboratory, operated by U. Chicago Argonne, LLC, for the US Department of Energy under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up, non-exclusive, and irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.