Tag Archives: GW

Yambo input file for GW calculations explained

Example of a yambo input file for GW calculation in a solid. In order to generate the following input file you can use the command “yambo -g n -p p -V par” with yambo 4.0.2 (and with yambo 3.4.2  “yambo -g n -p p”).   gw0 # [R GW] GoWo Quasiparticle energy levels ppa #… Read More

Reasonable parameters for Yambo calculations

Here I report some advices to choose reasonable parameters in order to converge different kind of calculations with the Yambo code. The following parameters are a reasonable recommendation. However you have to remember that convergence can be different from system to system, so you should check your calculations and not use the following parameters blindly…. Read More

New poster on GW renormalization of the electron-phonon interaction

Here my new poster that I will present to the PSI-K conference on the GW renormalization of the electron-phonon interaction. In this poster I summarize results from different group that used GW approximation to correct the electron-phonon coupling obtained from the Kohn-Sham Hamiltonian. Thanks to these corrections it was possible to reproduce and predict different… Read More

Nonlinear response of solids within the GW plus Bethe-Salpeter approximation

My new talk for the GDR-Corr is available online. In this talk I will present our new (probably not so new now) approach to calculate non-linear response in extended systems within the GW plus Bethe-Salpeter equation. I  put different references in the presentation that can be interesting for the reader.

Self-consistent GW on eigenvalues only with the Yambo code

Not working anymore in Yambo 4.5 but works in Yambo 5.x For molecules and also for molecular solids, the G0W0 approach often gives poor results. The main reason of this failure is  the DFT  starting point. In fact local or semi-local exchange correlation functionals give a too small gap compared with the experimental one, and… Read More

Strong second harmonic generation in SiC, ZnO, GaN two-dimensional hexagonal crystals from first-principles many-body calculations

We published a new paper on the second harmonic generation(SHG) in two-dimensional hexagonal crystals SiC, ZnO and GaN. The SHG is calculated within the so called GW plus Bethe-Salpter formalism, using a real-time implementation proposed by some of us. We found that these system present a large region with a strong SHG before the absorption… Read More

“GW renormalization of the electron-phonon coupling” talk at the Correlation Meeting 2014

Thanks to Francesco Sottile the video of my presentation at the “Correlation Meeting 2014” is online. In this talk I explain how GW can be used to correct the electron-phonon matrix elements, and improve the agreement with the experiments as Raman, phonons, band gap renormalization, superconductivity, etc…

Review on GW and Bethe-Salpeter for molecular systems

We just published a new review on GW and Bethe-Salpeter (BSE) for molecules. In the review we discuss electronic excitations both in TDDFT and  in the Green’s function approach.  The successes and failures of the different methods are presented. In particular we focused on charge-transfer excitations for which the photoexcited electron and the hole left… Read More

Efficient Gate-tunable light-emitting device made of defective boron nitride nanotubes

I published my first “Nature”, even if the lower level one, a Nature Scientific Reports: Efficient Gate-tunable light-emitting device made of defective boron nitride nanotubes: from ultraviolet to the visible Claudio Attaccalite, Ludger Wirtz, Andrea Marini & Angel Rubio Scientific Reports 3, Article number:2698 Boron nitride is a promising material for nanotechnology applications due to… Read More

Optical excitations in a paradigmatic model dipeptide

We just post on arxiv a new paper on the optical excitations in a paradigmatic model dipeptide, here in the figure. We studied local and charge transfer excitations by means of state of the art GW and Bethe-Salpeter equations as implemented in the FIESTA code. In particular we focused on the effect of self-consistency in… Read More