Difference between revisions of "Quasi-particle properties"

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== The HF approximation (yambo -x) ==
== The HF approximation (yambo -x) ==
As you have seen in the lectures or textbook the GW self-energy is separated into two components named exchange self-energy (Σx) and correlation self-energy (Σc).
As you have seen in the lectures or textbook the GW self-energy is separated into two components named exchange self-energy (Σx) and correlation self-energy (Σc):
[[File:Sigma.png|none|300px|caption]]
[[File:Sigma.png|none|200px|caption]]
We start by evaluating the exchange Self-Energy and the corresponding Quasiparticle energies (Hartree-Fock energies). It is important to note that this way we are adding the HF contribution in a perturbative way to previously calculated DFT energies (E=Eo+Σx-Vxc) and hence they will differ from a standard self-consistent HF calculation.
We start by evaluating the exchange Self-Energy and the corresponding Quasiparticle energies (Hartree-Fock energies).  
[[File:Sx.png|none|500px|caption]]
It is important to note that this way we are adding the HF contribution in a perturbative way to previously calculated DFT energies:
 
[[File:Ehf.png|200px|caption]] 
 
and hence they will differ from a standard self-consistent HF calculation.
Let's start by building up the input file for an HF calculation by typing:
 
yambo -x -V all -F hf.in

Latest revision as of 09:49, 23 March 2017

UNDER CONSTRUCTION (DV)

In this tutorial you will learn how to:

  • calculate quasi-particle correction in HF approximation
  • calculate quasi-particle correction in GW approximation
  • How to choose the input parameter for a meaningful converged calculation
  • How to plot a band structure including quasi-particle corrections

Prerequisites

The HF approximation (yambo -x)

As you have seen in the lectures or textbook the GW self-energy is separated into two components named exchange self-energy (Σx) and correlation self-energy (Σc):

caption

We start by evaluating the exchange Self-Energy and the corresponding Quasiparticle energies (Hartree-Fock energies).

caption

It is important to note that this way we are adding the HF contribution in a perturbative way to previously calculated DFT energies:

caption

and hence they will differ from a standard self-consistent HF calculation. Let's start by building up the input file for an HF calculation by typing:

yambo -x -V all -F hf.in