Yambo Post Processing (ypp)

YPP is a post-processing tool included in the Yambo distribution.
In this tutorial we present a non-exhaustive list of the things that can be calculated with this tool.

• Brillouin Zone:
  

-k p → write the k-point list in different format
-k q → write the q-point list in different format
-k s → generate shifted k-points grid
-k h → write the highest symmetry points in the BZ
-k r → generate random k-points in the BZ
-k e → generate regular k-points grids 
-map → map a fine grid of k-points on the coarse one, see Double-grid in Yambo

• Convertions:

-y  →     Remove symmetries not consistent with an external perturbation, see Real Time propagation with Yambo and Linear response in real-time
-qpdb g →  generate-modify quasi-particle(QP) database
-qpdb m →  merge quasi-particle(QP) databases
-qpdb e →  expand quasi-particle(QP) database in the full Brillouin zone(BZ)

• Plots:

-b → Select the momentum of the exciton you want to analize (default = 1)
-s w  → Plot electron wave-functions
-s d  → Plot electron density
-s s  → Plot electron density of states
-s m  → Plot electron magnetization
-s b  → Interpolate electronic bands using the approach of Ref., adding  -V qp includes the quasi-particle correction
-s c  → Plot the current density

 -e s  → Sort exciton according to their energy and dipole, see How to analyze excitons
 -e sp → Plot exciton spin
 -e a  → Write exciton coefficients amplitudes 
 -e w  → Plot excitonic wave-function for fixed hole position, see How to analyze excitons
 -e i  → Interpolate excitonic dispersion, requires BSE for all q-points, see How to analyze excitons
 -dipoles exc  →   Print excitonic dipoles, see How to analyze excitons
 -dipoles ip  →   Print Kohn-Sham dipole matrix elements
 -freehole   →  Plot excitonic wave-function with free hole position
 -avehole  → Plot excitonic wave-function with average hole/electron wavefunction, see  How to analyze excitons

• SOC:

  -soc   →  Perturbative SOC mapping

Special features in ypp_ph:

-g g → Read GKKP databases from QuantumEspresso, see Electron phonon coupling
-g d → Read double-grid for phonons, see Electron phonon coupling
-g p → Plot the module of the gkkp matrix elements

-p d → Phonon density of states
-p e → Electronic Eliashberg functions, see Electron phonon coupling

-e e → Excitonic Eliashberg functions, see  Optical properties at finite temperature
-e g → Exciton-phonon matrix elements (only diagonal part)
-e p → Phonon-assisted excitonic density of state,  Optical properties at finite temperature

Special features in ypp_nl:

-u → Analise the non-linear response, see Non-linear spectroscopy