Postdoctoral position in ab initio many-body condensed-matter theory

Institut Néel, CNRS and University Grenoble Alpes, Grenoble, France

Context and subject: While time-dependent density-functional theory (TD-DFT) stands as an extremely powerful and versatile approach to study condensed matter systems in the excited-state, the many-body Green’s function Bethe-Salpeter formalism is now being used by several groups worldwide both in physics and chemistry, curing some of the well-known TD-DFT deficiencies while offering the same computational scaling with system size [for a review, see e.g.  Blase, Duchemin, Jacquemin, Chem. Soc. Rev. 2018]. A serious limitation for its development lies in the lack of a formalism for calculating “analytic forces” in the excited states, dramatically hampering its ability to perform structural relaxation in the excited-state, closing the door to many interesting problems related to light emission, photo-catalysis, etc. The postdoctoral fellow will thus join an ongoing effort to develop many-body perturbation theories (the FIESTA initiative) with two main goals : (a) implementing real-space-grid Bethe-Salpeter formalisms to achieve cubic scaling, following a recent implementation of such a formalism at the many-body GW level [see Duchemin and Blase, JCTC 2021] and (b) developing analytic forces within the Bethe-Salpeter formalism with application to the emission of important chromophores. This project is part of a collaboration between Institut Néel, CNRS/Grenoble and IRIG, CEA/Grenoble for methodological aspects, together with Pr. Denis Jacquemin, CEISAM/University of Nantes, for applications.

Required skills : the ideal candidate will have a PhD in computational ab initio condensed-matter physics or chemistry with a strong taste for theory and formalisms. The hired postdoctoral fellow will be involved in the development of the Fiesta code under the guidance of the developers (Xavier Blase and Ivan Duchemin). 

Offer : the postdoctoral position is opened for up to 2 years depending on the level of qualification. The funding agency is the French National Research Fund (ANR) within the framework of the BSE-Forces project.

Location : the candidate will join the Condensed Matter Theory group at Institut Néel, Grenoble, one of the largest CNRS condensed matter physics lab in France located on the “scientific polygon,” in close collaboration with the neighbouring L_Sim group at CEA/Grenoble. The scientific polygon, with its CNRS, CEA and University labs, its European synchrotron, neutron facility, and high magnetic field lab, is a very dynamical and worldwide attractive environment in condensed matter physics, ideally located close to the Alps. 

Contact : Xavier Blase, Institut Néel, Grenoble, France  ([email protected])  and Ivan Duchemin, L_Sim, CEA, Grenoble, France  ([email protected])

Web sites:   http://perso.neel.cnrs.fr/xavier.blase/                http://perso.neel.cnrs.fr/xavier.blase/fiesta/           https://www.mem-lab.fr/en/Pages/Portrait/Ivan-Duchemin.aspx