High Pressure Physics

Mario Santoro

Mo, 11 Apr 2016, at 10:00. Aula Querzoli

PDFs of the presentations A and B

I will present on general aspects of high pressure (HP) physics (0-300 GPa), such as where HPs are encountered in the universe, what kind of materials deserve the highest interest, what can be studied in the laboratories, etc.. Indeed, high pressure science covers nowadays a broad range of different research fields such as fundamental condensed matter physics and chemistry, earth and planetary science, and materials science. I will briefly show a few recent highlights on phase diagrams of simple systems, including remarkable phenomena as the insulator-to-metal transition, the metal-to-insulator transition [1], molecular transformations in simple substances such as O2 and CO2 [2], and fluid-fluid transformations. I will then introduce the diamond anvil cell (DAC), which can be driven in the Mbar range and simultaneously cooled down to 4 K, or resistively heated up to 1000-1200 K and laser heated up to 5000 K-6000 K. Finally, I will show several among the major techniques for in situ material investigations in DACs: Raman and Infrared spectroscopy, and laboratory and synchrotron based X-ray diffraction.

[1] Y. Ma, M. Eremets, A. R. Oganov, Y. Xie, I. Trojan, S. Medvedev, A. O. Lyakhov, M. Valle, and V. Prakapenka, Transparent dense sodium, Nature 458, 182 (2009)

[2] M. Santoro, F. A. Gorelli, R. Bini, J. Haines, O. Cambon, C. Levelut, J. A. Montoya, and S. Scandolo, Partially collapsed cristobalite structure in the non molecular phase V in CO2, Proc. Natl. Acad. Sci. U. S. A. 109, 5176 (2012)