X-Treme / X07MA:
X-ray absorption spectroscopy at high magnetic field and low temperature

The X-Treme beamline produces a high flux of soft x-rays with variable polarization (circular left, circular right and linear polarization in any angle between 0 and 90 degrees) from an Apple-II undulator source.

The end station is equipped with a superconducting 2D vector magnet operating at 7 T single direction or 2 T vectorial field and a 2 K sample insert. The end-station is also equipped with an in-situ sample preparation system and a variable-temperature scanning tunneling microscope.

The beamline mostly focuses on measurements involving x-ray magnetic circular (XMCD) and linear dichroism (XLD, XMLD) at transition metal L_2,3-edges (transition 2p -> 3d), lanthanide M_4,5 edges (transition 3d -> 4f) and oxygen or nitrogen K-edges (transition 1s -> 2p). Typical systems studied are single atoms on surfaces; molecules or single-molecule magnets in bulk or on surfaces; superlattices and ultra-thin films. Different detection modes are available: total electron yield, total fluorescence yield, transmission and x-ray excited optical luminescence.