A5086897754- Advanced Chemical Physics Studies
- Quantum and electron transport phenomena
- Physics of Superconductivity and Magnetism
- Machine Learning in Materials Science
- Rare-earth and actinide compounds
- High-pressure geophysics and materials
- Boron and Carbon Nanomaterials Research
- Electronic and Structural Properties of Oxides
- Muon and positron interactions and applications
- Thermodynamic and Structural Properties of Metals and Alloys
- Laser-Matter Interactions and Applications
- Nuclear Materials and Properties
- Organic and Molecular Conductors Research
- Quasicrystal Structures and Properties
- Cold Atom Physics and Bose-Einstein Condensates
- Chemical and Physical Properties of Materials
- Intermetallics and Advanced Alloy Properties
- Surface and Thin Film Phenomena
- Spectroscopy and Laser Applications
- 2D Materials and Applications
- Chalcogenide Semiconductor Thin Films
- Spectroscopy and Quantum Chemical Studies
- Quantum optics and atomic interactions
- Crystallography and molecular interactions
- Thermal Expansion and Ionic Conductivity
Université Paris-Saclay
2017-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2019-2024
CEA Paris-Saclay
2023-2024
CEA DAM Île-de-France
2019-2024
Centre National de la Recherche Scientifique
2011-2021
Institut de minéralogie, de physique des matériaux et de cosmochimie
2019-2021
Sorbonne Université
2011-2021
Institut de Recherche pour le Développement
2019-2020
École Normale Supérieure Paris-Saclay
2017-2019
Laboratoire de Physique Théorique de la Matière Condensée
2014-2017
abinit is probably the first electronic-structure package to have been released under an open-source license about 20 years ago. It implements density functional theory, density-functional perturbation theory (DFPT), many-body (GW approximation and Bethe–Salpeter equation), more specific or advanced formalisms, such as dynamical mean-field (DMFT) “temperature-dependent effective potential” approach for anharmonic effects. Relying on planewaves representation of wavefunctions, density, other...
A phase diagram of gold is proposed in the [0; 1000] GPa and 10 000] K ranges pressure temperature, respectively, topologically modified with respect to previous predictions. Using finite-temperature ab initio simulations nonequilibirum thermodynamic integration, both accelerated by machine learning, we evaluate Gibbs free energies three solid phases previously proposed. At room face-centered cubic (fcc) stable up $\ensuremath{\sim}500\text{ }\text{ }\mathrm{GPa}$ whereas body-centered (bcc)...
We calculate the ground state phase diagram of homogeneous electron gas in two dimensions within Hartree-Fock approximation. At high density, we find stable solutions, where electronic charge and spin density form an incommensurate crystal having more sites than electrons, whereas commensurate Wigner is favored at lower densities, rs> 1.22. Our explicit calculations demonstrate that Fermi liquid -- though being exact stationary solution equations never gas.
We calculate the ground state phase diagram of homogeneous electron gas in three dimensions within Hartree-Fock approximation and show that broken symmetry states are energetically favored at any density against Fermi with isotropic surface. At high density, we find metallic spin-unpolarized solutions where electronic charge spin form an incommensurate crystal having more sites than electrons. For r(s)→0, our approach pure spin-density waves, whereas commensurate Wigner is lower densities,...
We determine the correlation energy of BN, SiO$_2$ and ice polymorphs employing a recently developed RPAx (random phase approximation with exchange) approach. The provides larger more accurate polarizabilities as compared to RPA, captures effects anisotropy. In turn, energy, defined an integral over density-density response function, gives improved binding energies without need for error cancellation. Here, we demonstrate that these features are crucial predicting relative between low-...
In a previous work it was shown that the inclusion of exact exchange is essential for first principles description both electronic- and vibrational properties TiSe$_2$, M. Hellgren et al. [Phys. Rev. Lett. 119, 176401 (2017)]. The $GW$ approximation provides parameter-free screened but usually employed perturbatively ($G_0W_0$) making results more or less dependent on starting point. this work, we develop quasi-self-consistent extension $G_0W_0$ based random phase (RPA) optimized effective...
Several long-debated dynamical and elastic unusual properties of $\ensuremath{\delta}$-Pu are captured within a unified theoretical framework. This outcome is achieved owing to machine learning accelerated ab initio simulations enabling fine description strong electronic correlations explicit temperature effects. First, the experimental negative thermal expansion equilibrium volume pure correctly depicted. Second, extreme softening phonon spectrum, related huge anharmonic effects,...
In a previous letter, L. Baguet et al., (Phys. Rev. Lett. {\bf 111}, 166402 (2013)), we presented the ground state phase diagram of homogeneous electron gas in three dimensions within Hartree-Fock approximation yielding incommensurate crystal states at high density. Here, analyze properties these solutions. particular, density find universal behavior strongly supporting existence spin wave state.
We investigate the adiabatic approximation to exact-exchange kernel for calculating correlation energies within adiabatic-connection fluctuation-dissipation framework of time-dependent density functional theory. A numerical study is performed on a set systems having bonds different character (H$_2$ and N$_2$ molecules, H-chain, H$_2$-dimer, solid-Ar H$_2$O-dimer). find that can be sufficient in strongly bound covalent systems, yielding similar bond lengths binding energies. However,...
Studying the jellium model in Hartree-Fock approximation, Overhauser has shown that spin-density waves (SDWs) can lower energy of Fermi gas, but it is still unknown whether these SDWs are actually relevant for phase diagram. In this paper, we give a more complete description SDW states. We show modification ansatz explains behavior at high density compatibly with previous simulations.
In this paper, we review the possibility of periodic ground states two‐ and three‐dimensional electron gas at high intermediate densities. At Hartree–Fock level, obtain explicit solutions all densities having lower energies than homogeneous Fermi gas. high‐density region, electrons only partially fill up band approaching spin density waves as predicted by Overhauser. Preliminary variational Monte Carlo calculations on polarized two‐dimensional confirm existence these new types states.