One of the main objectives of today’s ongoing research is the design of new materials with specific properties for technological applications. A successful material modeling requires a profound understanding of the physics behind the properties of the systems, which can be reached only through a strong interplay between theory and experiments. This sets the stage for the present project, which is primarily theoretical, but in which the comparison with the experiments will play an essential role.
The aim of DENE is the development of a theoretical tool for the description of neutral excitations that are directly probed in absorption, electron energy loss and inelastic X-Ray scattering experiments. It is focused on the description of dynamical effects beyond the quasi particle picture that are not taken into account in the present theories with application to challenging problems namely: (i) the correct description of the spectrum in systems where dynamical effects are not negligible as metals and strongly
correlated insulators, (ii) the description of multiple excitations that are not included in a quasi particle picture, (iii) the understanding of the role played by electronic correlations on the lifetime of neutral excitations. In particular the project will be mainly focused on the understanding of multiple excitations in strongly correlated transition metal oxides.

Publications related to the project:

1) Excitons in van der Waals materials: from monolayer to bulk hexagonal boron nitride.
Jaakko Koskelo, Giorgia Fugallo,Mikko Hakala,Matteo Gatti, Francesco Sottile, and Pierluigi Cudazzo.
Phys. Rev. B 95 035125 (2017).

2) Negative plasmon dispersion in 2H-NbS2 beyond charge-density-wave interpretation.
Pierluigi Cudazzo, Eric Müller, Carsten Habenicht,Matteo Gatti, Helmuth Berger, Martin Knupfer, Angel Rubio, Simo Huotari.
New Journal of Physics 18, 103050 (2016).

Talk at international conferences:

1) October 2016: Talk at Annual meeting of GDR-I GNT "Graphene and Nanotubes: Science and applications", Saint Pierre d'Oléron (France)
"Exciton band structure in two dimensional materials".

2) September 2016: Invited Talk at Marseille Condensed Matter 2016: Optics and Magnetism, Marseille, France
"Exciton band structure in two-dimensional materials".
3) June 2016: Talk at JEELS 2016 10eme edition des Journées de l’EELS. Tarragona (Spain).
"Exciton band structure in two dimensional materials".

4) May 2016: Talk at the Roscoff Meeting "The first general meeting of the GDR RES"T, Roscoff (France).
"Plasmon and exciton dipersion in two dimensions".

5) September 2015: Talk at the Discussion Lavoisier "Nouveaux Materiaux bi-dimensionnels: dichalcogenures de metaux de transition et nitrure de bore", Toulouse (France).
"Plasmon and exciton dispersion in two dimensions".

6) September 2015: Poster at the PsiK conferemce, San Sebastian (Spain).
"Plasmon and exciton dispersion in two dimensions".

ACKNOWLEDGMENTS
This research was supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 660695.