The investigation of matter under extreme conditions is one of the natural strongholds of a third-generation synchrotron radiation source. High-pressure research benefits from the large number of photons in spots of 10 µm size or less. The highest pressures, in the 300 GPa region, can thus be attained using diamond anvil cells. This is one of the branches which is followed intensely at beamlines ID9 and ID30. High pressures are combined with laser heating, which again profits from the small size of the samples. While a first experimental setup involving laser heating was operated successfully in collaboration with competent users, the ESRF is now setting up a much more powerful facility.

The other branch of high pressure research makes use of the Paris-Edinburgh cell which allows us to exert a pressure of up to 2 GPa on several mm3 of material. In these cells, the synthesis of materials can be investigated in real time, such as the formation of hard B, N, C compounds, the crystallisation of fullerenes, and the molten forms of iron under pressure. The latter research is of great geophysical relevance.

This year the ESRF has acquired a new large-volume Paris-Edinburgh cell which will be used primarily on BM29. This cell is both compact and light (25 kg), which facilitates its transfer and installation at several other beamlines. Thus, among others, it can be used for EXAFS, nuclear scattering and inelastic scattering experiments.