My main areas of interest are mineral physics and materials research. Mineral physics is the study of the chemical and physical properties of minerals applied to problems in the evolution and dynamics of planetary bodies. We use the diamond anvil cell to study simple materials as well as minerals at high pressures. The pressures that we can achieve are in excess of 200 GPa or two million atmospheres which corresponds to 3,500 km depth in the Earth. By using a laser to heat the samples we can reach temperatures of 6000 K while the samples are at high pressures. These types of experiments allow us to perform a wide variety of petrologic experiments at lower mantle pressures and temperatures. For instance we measure solid-solid and solid-liquid phase transformations as a function of temperature and pressure, as well as major and minor element partitioning between coexisting phases.

Diamonds are transparent to a wide range of electromagnetic radiation, which makes them a very good window material for a wide variety of spectroscopic techniques. In particular we are interested in infrared, Raman and Brillouin spectroscopy on Earth materials, since the vibrational spectroscopy can place important constraints on the thermodynamic properties of these materials. Brillouin scattering is used to measure elastic constants of materials at high pressures. Synchrotron radiation is used to measure equations of state of materials as a function of temperature and pressure.

1986 Ph.D., University of California, Berkeley (Geophysics)