Welcome to the mineral physics group
The mineral physics group lead by Prof. Motohiko Murakami seeks at measuring the physical properties (elasticity, density, etc.) of minerals and materials that constitute the Earth and planetary interiors.
Experimental mineralogy aims at reproducing the conditions that can be found in deep planetary interiors and at measuring in situ the properties of materials (minerals, crystals, magmas, etc.) that constitute the interiors of planets. To access pressures and temperatures of the deep Earth´s mantle (P >30 GPa, T> 1000 K) we use the diamond-anvil cell (DAC) combined with laser or resistive heating to generate such conditions. Indeed, diamond is the hardest known material and can sustain extreme stresses allowing to generate ultra-high pressures. In addition, diamond is transparent to a large spectrum of radiation, from the visible to X-rays, enabling to conduct in situ spectroscopy (Raman, FTIR) or to solve the structure of minerals using X-ray diffraction.
At ETH, we develop a unique combination of laser-heating set-up for the DAC coupled with in situ Raman and Brillouin spectroscopy. This combination of techniques allows to measure pressure and identify newly formed phases and retrieve temperature through black body radiation spectroscopy with the Raman set-up. Using the Brillouin spectroscopy, we can measure the elasticity and sound wave velocities through the minerals or material in situ at high pressure and temperature. The precise determination of pressure, temperature, volume and sound wave velocities are keys to build compositional and physical models of deep planetary interiors.