Alexandre Courac (Kurakevych) is Associate Professor (MCF) at Sorbonne University – IMPMC, where he conceptualizes and synthesizes new materials under extreme pressure–temperature conditions. His research combines in‑situ synchrotron diffraction and thermodynamic modeling to develop scalable pathways to superhard and optoelectronic solids, such as quasi‑direct band‑gap silicon allotropes. In 2017–2022 he was a member of the Institut Universitaire de France (IUF), leading the project Synthesis of Silicon Allotropes, which provided the first high‑purity crystals of hexagonal and clathrate phases and enabled systematic thermodynamic modeling of their stability. He was a principal investigator of the ANR project POLYCARBS (2017–2021), and is task leader in SUPERSTRONG (2022–2026) and BCSi (2021–2024).
Originated from the Crimea peninsual, he began research as a student at the Institute for Superhard Materials in Kiev, NAS of Ukraine (V. Solozhenko) and at the University of Hawaii high‑pressure group (M. Manghani & L.C. Ming), publishing his first articles during his Master’s (2002). His doctoral thesis (Université Paris Nord, 2007, funded by CNRS) on ultra‑hard boron–carbon–nitrogen–oxygen phases laid the foundation for his expertise in high‑pressure chemistry (director V. Solozhenko). From 2011 to 2013, he was postdoctoral fellow at Carnegie Institution of Washington (Geophysical Laboratory, now EPL), after ear lier CNRS postdoc and ATER positions in Paris (2007–2011). He obtained his HDR (Habilitation à Diriger des Recherches) in Physics at Université Pierre & Marie Curie / Paris 6 in 2017. Today his trajectory reflects continuity from fundamental phase diagrams to the design of functional crystals, training of young scientists, and leadership of international collaborations across Europe, the US, and Asia.
Researcher ID: ORCID • Google Scholar
The contribution of A. Courac is internationally recognized in high-pressure high-temperature (HPHT) synthesis and high-pressure crystallography, working at the interface of solid-state chemistry, physics of materials, and crystallography. Major contributions to ultrahard light-element materials include the discovery of boron subnitride B₁₃N₂, first reported in Acta Crystallographica C, and key results on boron allotropy published in Nature (2009), including an allotrope exhibiting record hardness among boron polymorphs. Record performance in a non-carbon ultrahard material was established for nanostructured cubic boron nitride (nano-cBN) in Advanced Materials, accompanied by patents with IMPMC and followed by continued studies of structure–property relationships and phonon-related behavior. A second high-impact research direction emerged from the discovery of the high-pressure clathrate Na₄Si₂₄ (Crystal Growth & Design), which enabled the pathway toward the zeolite-type silicon allotrope Si₂₄, published in Nature Materials (2015) and supported by multiple patents. These results collectively position high pressure as a tool not only for accessing extreme states of matter, but also for delivering new crystal structures, compositions, and nanostructures with advanced mechanical and functional properties.
The research program is structured around three interdisciplinary axes that jointly enable rational materials discovery under pressure. (1) In situ crystallography: synchrotron X-ray diffraction under extreme conditions is used to identify transient intermediates, determine crystal structures and equations of state, and follow kinetics of transformations in real time, using large-volume presses and dedicated sample environments. These experiments are carried out with large-volume devices at IMPMC and through beamline campaigns at SOLEIL and the ESRF, where in situ diffraction can be combined with complementary measurements to constrain microstructure, texture, and stability fields. (2) Chemical thermodynamics: pressure-dependent phase stability and chemical reactivity are addressed through thermodynamic analysis and modelling, including CALPHAD/Thermo-Calc approaches, to build consistent descriptions of multicomponent systems (boron-rich ceramics, Si-based compounds) and to translate experimental constraints into predictive phase diagrams. (3) Phase transformations and crystal growth: emphasis is placed on mechanistic understanding—nucleation, growth, metastability, and recovery pathways—linking transformation sequences to final microstructures and to properties such as hardness, toughness, and electronic functionality. Across these axes, high pressure is treated as a quantitative variable that reshapes thermodynamics and reaction pathways, enabling the targeted synthesis of (i) new crystal structures, (ii) new compositions, and (iii) pressure-stabilized nanostructures. The portfolio spans ultrahard carbides/borides/nitrides and silicon allotropes of technological interest; synthesis outcomes—successful or not—are systematically leveraged to refine phase boundaries, constrain reaction routes, and guide next-generation experiments toward reproducible crystals and scalable synthesis windows.
Role: Work Package Manager (2022–2026)
Role: Work Package Manager (2021–2025)
Role: PI (2017–2022)
Role: PI (2017–2021)
Principal Investigator. Alexandre Courac (Kurakevych) — Associate Professor, Sorbonne University — IMPMC. Focus: HPHT synthesis; in‑situ synchrotron diffraction; CALPHAD; HP calorimetry.
ED297 — Scientific Integrity Training. At doctoral and Master levels, I deliver workshops on good research practices, authorship, data management, conflict‑of‑interest prevention, and responsible conduct in experimental design and reporting. Sessions combine case studies from materials science with checklists for lab notebooks, FAIR data, and preregistration when appropriate. Goal: align lab routines with institutional and EU guidance on integrity, reproducibility, and open science.
Professional Orientation (OIP). For L2–L3 students, active workshops on employability: timed self‑presentations, CV/cover‑letter clinics, interview rehearsals, and networking assignments (professional interviews prepared in class). These activities connect physics with job‑market expectations and help students articulate skills for internships and early careers.
Core Teaching — General Physics, Thermodynamics, Materials & Labs. Teaching in L1–L3 and supervision of L3 internships and M1/M2 theses in high‑pressure materials. Practical modules emphasize instrumentation (oscilloscopes, function generators, microcontrollers, sensors, video analysis) and reproducible analysis in Python. Evaluation is transparent and criterion‑based, fostering the translation of physical models into engineering practice.
