Speaker: Eric Pellegrin, CELLS-ALBA
Program Description:
ALBA BL29, “BOREAS”, is a soft X-ray beamline dedicated to polarization-
dependent spectroscopic investigations of advanced materials, enabling techniques such as
XAS, XMCD, XMLD, and resonant scattering & reflectivity. It delivers high flux with high
resolution, so that spectra of elements with minute concentrations (i.e., 10
-4
atomic layers) of
ferromagnetic elements are routinely performed within 2-3 minutes. Typical experiments
include studies of isolated TM and RE magnetic atoms at surfaces or incorporated in organo-
metallic molecules or 2D materials. Samples can be prepared using in situ surface science
capabilities, and eventually characterized using an in situ STM. Absorption spectra from
around 80 eV up to 4 keV can be taken using circular/elliptical polarization, yielding rather
exclusive opportunities at the L- and M-edges of 4d and 5d transition metals, respectively.
BOREAS is equipped with two state-of-the-art end-stations: The first one is a high-field
vector magnet for soft X-ray techniques such as XAS, XMCD, or XMLD. The second end
station is a UHV reflectometer for complementary approaches including resonant soft X-ray
reflectivity, resonant magnetic scattering, and GISAXS, under applied magnetic fields up to 2
Tesla and between 20 to 400 K. The beamline instrumentation and capabilities will be
reviewed in this talk, including a few salient scientific results.
