92
SOLEIL
HIGHLIGHTS
2013
When synchrotron light meets extraordinary materials, outstanding results often appear.
This statement is well illustrated in the Hard-Condensed matter section of the 2013 SOLEIL
Highlights that sheds light on materials with remarkable properties, often using
a multimodal, multiscale approach with the synchrotron as a key ingredient.
First, Bertrand et al. have used an improved microscope setup at DISCO to study zinc
oxide white pigment. If the pigment shows an apparent homogeneous photoluminescence
at the macro scale, the results clearly reveal that it is highly heterogeneous at the micro-
and nano-scale.
Bonilla et al on the other hand performed XAS and XRD at SAMBA and SIXS, in par with
TEM and SQUID to investigate the structure of self-assembled vertical epitaxial Co-Ni
alloy nanostructures grown by a combinatorial approach. The XRD data confirms the
full epitaxial relationship between the nanowire and the substrate while XAS establishes
the fcc structure of the alloys, hence validating the synthesis method.
At smaller scale, Corradini et al. have characterized an assembly of isolated Fe cage
molecules deposited on a gold surface by STM, XPS and XMCD realized on DEIMOS.
Their results demonstrate that the magnetocaloric effect is preserved in single molecules
deposited on a substrate, opening the way for magnetic cooling process at the molecular
level.
In functionalized materials, Cunha et al. have carried out a vast survey of the drug
encapsulation and release from biocompatible porous metal-organic frameworks (MOF)
while Hervieux et al. demonstrated the oxygen storage ability of a layered oxide material
and its cycling possibility using XRD and other lab-based techniques. In both cases,
high-resolution diffraction performed at CRISTAL helped reveal the structural changes
at the nm scale during the process, a key step towards improving the uptake mechanism.
More fundamentally, Chaix et al. developed synchrotron THz experiment at AILES to study
a chiral langasite compound. The results disclose a new kind of low energy excitations
both magnetic and electric active, and associated to atomic vibrations. These findings
demonstrate that atomic vibrations can acquire a magnetoelectric character, thus opening
new routes to carry and process information.
Finally, Peron et al. used soft X-ray resonant scattering at SEXTANTS to study the
magnetization of lithography produced artificial spin ice comprising a dense array
of nanomagnets. The resonant scattering process when observed in a wide portion
of the reciprocal space provides a direct mean to extract the number of reversed moments.
As shown here, the need to combine different techniques on the same sample is likely
to become more urgent in the future. This applies to the synchrotron studies too.
The vast range of techniques developed in The Hard Condensed Matter section shall
be extremely useful to that aim.
Jean-Pascal Rueff
Head of the "Physics and Chemistry of Condensed Matter,
Earth Sciences" Scientific Section
PHYSICS AND CHEMISTRY OF CONDENSED MATTER,
EARTH SCIENCES
