High-pressure x-ray diffraction

The use of high pressure as a thermodynamic parameter in the study of solid state phenomena has become increasingly important for basic and applied physics as well as for geophysics. By varying pressure and/or temperature we are able to identify critical thermodynamic coordinates and to monitor how materials transform from one phase to another. In particular, attention is devoted to structural changes, the equation of state, fluctuating valence states, insulator-metal transitions, and the influence of pressure on high Tc superconductors.
As for technological applications of high pressure research, one may mention the synthesis of new super hard materials.
Our group has pioneered the use of energy dispersiv methods for high pressure powder x-ray diffraction, in particular in conjunction with synchrotron radiation and the diamond anvil cell. We are also performing high-pressure, high-temperature studies using a large-volume multi-anvil cell. On the technical side, we are developing high-resolution methods based on the image-plate detector.