MY RESEARCH

My research focuses on understanding the functioning of the planets, from their surface to their uttermost depth, from their cataclysmic formation to their silent death. I adopt an interdisciplinary approach by studying in the laboratory the physics and chemistry of planetary minerals (i.e. silicates, oxides and metallic alloys).  

I hold a Master in Earth Sciences with a major in Mineralogy and Geochemistry and a PhD in Geology. The overarching question been addressed by my PhD was the geological history of the Nakhlite, a group of Martian meteorites 1.3 Ga old. These included the magmatic processes at the origin of the meteorites and the nature of the aquifer that circulated recently throughout the shallow bedrock on Mars. For example, I have extracted hydrogen on a manual line by reduction over chromium, and measure water abundances and isotopic signatures on secondary and normally anhydrous primary minerals on a dynamic dual inlet IRMS. The results were then integrated with information from Mars rovers and landers in order to build a comprehensive model of the evolution of the Martian hydrosphere with predictions relevant to future exploration.


Today, my research focuses on investigating the fundamental properties of natural materials under pressure using the diamond anvil cell, with a focus on how these properties change as the conditions become more and more extreme. These properties include crystal strength, elastic moduli, vibrational properties, electronic properties and transport behaviour (thermal and electric conductivity). Structural analysis is a key theme of my work. Using x-ray diffraction at international synchrotron facilities and the laser-heated diamond anvil cell, I determine crystal structures and stability fields of key minerals to establish phase diagrams. Then I examine how these findings can inform our understanding of the various Earth systems where extreme pressures and temperatures were commonplace.


My first post-doctoral position was part of the NERC funded Deep volatile Consortium ‘The Volatile Legacy of the Early Earth’ and was aimed at investigating the cycling of volatile compounds in the deep Earth to better understand how the Earth developed and sustained a habitable exosphere. I have used simulation experiments in the diamond anvil cell in conjunction with Raman spectroscopy, X-ray diffraction at synchrotron facilities and thermodynamic modelling. For example, I have investigated the partitioning of H2O in a deep magma ocean during core formation with implications for the formation of a proto-atmosphere and long-term cycling of hydrogen in the deep Earth. I have also investigated the effects of impurity elements such as carbon, nitrogen, sulfur and silicon on the structure and phase stability of metallic iron and their thermoelastic properties under high-pressure conditions to help better understanding the nature of the light elements in the Earth core.

Pressure is a thermodynamic variable that has the capacity to change the physical properties of materials. Complex atomic structures and unexpected physical properties and phenomena have emerged under extreme pressure, some of which are unlike anything observed at ambient conditions. My current post-doctoral position is part of a Swedish research project called Functional Quasicrystal supported by the Knut and Alice Wallenberg Foundation (KAW).  Quasicrystals (which are now found in nature) are complex intermetallic alloys constructed from large clusters of icosahedral symmetry which cannot have 3D periodicity.  In such structure, electrons and phonons are not affected by a periodic potential, which has consequences on their physical properties. My contribution to the project is to investigate the unique electronic properties of quasicrystals using pressure to characterize fundamental correlations between aperiodic atomic structure and novel electronic properties.

Synthesis of novel materials with technologically useful features is an important line of scientific interest for high-pressure experimental research. Another of my research interests is to understand why some thermoelectric materials (including the quasicrystals) show drastic enhancements of their properties at high pressure, so as to help create better performing thermolectrics. The ability to exploit quasicrystals is still at a very young phase, increasing technical sophistication (such as applying pressure) could lead to some unexpected application development in the future. Comprehension of the mechanisms of formation and stabilization of quasicrystals is the first step in handling them towards desired ends. Natural quasicrystals represent today the purest form of quasi-crystalline matter ever observed. Unlike laboratory-grown quasicrystals, they are not affected by phasons, quasi-particles that distort the crystalline structure. Understanding the processes that have formed and stabilized perfect (nature-made) quasicrystals in outer space could fill a big gap in our knowledge of solid-state physics.

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