Warm Dense Matter (WDM) at conditions of near-solid densities (0.01 to 10g/cc) and temperatures between 1eV and 100eV is believed to exist naturally in the cores of giant planets such as Jupiter and Saturn. Understanding the physics of these extreme conditions may help elucidate the history of the Solar System. This regime also occurs in plasmas produced by radiative irradiation of solids. Thus, a knowledge of the properties of WDM is important for technological developments such as plasma sources of X-rays and Inertial Confinement Fusion.
WDM physics is an exciting field for research. Theoretical modeling is difficult: electron degeneracy and strong ion-ion coupling mean it cannot be modelled either as classical plasmas or solids. In the laboratory, it can be produced by irradiating solids with optical lasers or X-ray fluxes. In our group we use facilities such large laser systems at the Central Laser Facility (VULCAN and Astra lasers), Ecole Polyechnique (LULI2000 laser) and ILE Osaka (Gekko laser) along with out colleagues in collaborating goups. We have also started to use the FLASH XUV Free electron laser (FEL) facility in Hamburg. The diagnostic techniques we use centre mainly about X-ray scattering as a way of elucidating the microscopic structure but we also work on X-ray and XUV emission spectroscopy and development of laser-plasma sources of ultra-fast X-ray bursts down to picosecond timescales (a picosecond is a millionth of a millionth of a second).