Jul 1 2013
Johan Chang has received the 2013 Lewy-Bertaut prize in recognition of his outstanding contributions to the quest for understanding cuprate superconductors. The prize nomination was motivated by his ingenious use of the complementarity of neutron- and X-ray scattering on the so-called stripe phases (spin and charge density waves).
The Bertaut prize honours the late Erwin Felix Lewy Bertaut in memory of his scientific achievements and cornerstones in crystallography and in neutron scattering. It is awarded to a young European scientist in recognition of notable experimental, theoretical, or methodological contributions in the field of investigation of matter using crystallographic or neutron scattering methods.
Johan Chang’s work has concentrated on the problem of high temperature superconductivity in layered copper-oxide materials -- a phenomenon that stands unexplained for more than two decades. A multi-disciplinary approach using transport, electron spectroscopy, and scattering techniques has lead to considerable experimental progress. In particular, the combination of neutron and x-ray scattering techniques in high magnetic fields, have lead to significant advances on this problem. The discovery of charge density wave order in the archetypal superconductor YBa2Cu3O7-x was for example found by hard x-ray diffraction. Field-induced magnetism and quantum critical spin dynamics in concert with high temperature superconductivity was revealed by neutron diffraction and spectroscopy. Johan Chang has also made contribution to the field of vortex physics using small angle neutron scattering. For more detail on Dr. Chang’s work, please visit this web address.
The rising career of Dr. Chang is an excellent example of the Swiss education and research system’s ability to produce and retain the future generation of leading researchers. He obtained his PhD at the Paul Scherrer Institute, added new skills and high profile publications during a postdoctoral fellowship with Prof. Louis Taillefer at University of Sherbrooke, and became an SNF-Ambizione fellow at EPFL in September 2012, hosted by Laboratory for Quantum Magnetism.