HDR d'Oleksandr Kurakevych

Oleksandr Kurakevych, maître de conférences, équipe DEMARE, soutient son HDR le vendredi 19 mai 2017 à 14 h 30 dans la salle de conférences de l'INSP - Barre 22-23 - 3e étage - Salle 317

« New dimensions for design and synthesis of high-pressure materials »

Figure

Electronic structure of silicon allotrope Si-III. The insert shows the crystal structure (top) and infra-red photon absorption spectrum (bottom).

Abstract

Carbon-, boron- and silicon based materials have recently found a renaissance due to the possibility to incredibly diversify their crystal structures and compositions under high pressure. The thesis describes the last-decade experience of the author in high-pressure synthesis of such materials and is focused on the promising methodological approaches to expand the domains of possible materials for new applications. The thesis presents the “high pressure” materials from the thermodynamic and alternative points of view, and discuss possible mechanisms of their formation. The formalized description of both “design” and recent advances in high pressure synthesis is given. After that, principal directions of modern high-pressure materials design are described, i.e. (i) advanced superhard materials – boron-rich solids, and (ii) new axis - recently proposed by the author and its collaborators – optoelectronic (quasi-) direct bandgap silicon materials (from ultra-narrow bandgap of ~30 meV for to infra-red photonics, to the ideal value solar cell of ~1.3 eV) that cover a wide range of possible applications.

Jury

Konstantin KAMENEV - Professeur (The University of Edinburgh) - Rapporteur
Domingo MARTINEZ-GARCIA - Professeur (University of Valencia) - Rapporteur
Jean-Paul ITIE - Directeur de recherche (Synchrotron SOLEIL) - Rapporteur
AlfonsoSAN MIGUEL  - Professeur (Université Lyon 1) - Examinateur
Dominique VREL - Directeur de Recherche (LSPM) - Examinateur
Massimiliano MARANGOLO  - Professeur (UPMC) - Examinateur