Nonequilibrium absorption in bulk silicon: Difference between revisions
(Creating a tutorial on nonequilibrium optical properties) |
m (Structure of the database) |
||
| Line 1: | Line 1: | ||
In this tutorial you will learn the basic concepts for computing changes in the optical properties of a semi-conductor in presence of a non-equilibrium electrons and holes distribution in conduction and valence band respectively. This tutorial is based on the results published in Phys. Rev. B<ref name="sangalli2016"/> | In this tutorial you will learn the basic concepts for computing changes in the optical properties of a semi-conductor in presence of a non-equilibrium electrons and holes distribution in conduction and valence band respectively. This tutorial is based on the results published in Phys. Rev. B<ref name="sangalli2016"/> | ||
<span style="color:red">Under construction</span> | |||
= The material: Silicon = | = The material: Silicon = | ||
We will study nonequilibrium absorption in bulk silicon. The same material used for this [Silicon|GW tutorial] | We will study nonequilibrium absorption in bulk silicon. The same material used for this [Silicon|GW tutorial] | ||
* [http://cst-www.nrl.navy.mil/lattice/struk/a1.html FCC] lattice | * [http://cst-www.nrl.navy.mil/lattice/struk/a1.html FCC] lattice | ||
| Line 18: | Line 18: | ||
= Tutorial files and Tutorial structure = | = Tutorial files and Tutorial structure = | ||
Follow the instructions in [[Tutorials#Files]] and download/unpack the <code>Silicon.tar.gz</code>. | Follow the instructions in [[Tutorials#Files]] and download/unpack the <code>Silicon.tar.gz</code>. | ||
Once the tutorial archive file is unzipped the following folder structure will appear | Once the tutorial archive file is unzipped the following folder structure will appear | ||
COPYING README Silicon/ | COPYING README Silicon/ | ||
with the Solid_Si folder containing | with the Solid_Si folder containing | ||
> ls Silicon/ | > ls Silicon/ | ||
PWSCF/ YAMBO/ | PWSCF/ YAMBO/ | ||
In the Pwscf folder the student will find an input/output directory with input/output files for pw.x. The Silicon pseudopotential file is also provided. | In the Pwscf folder the student will find an input/output directory with input/output files for pw.x. The Silicon pseudopotential file is also provided. | ||
> ls PWSCF/ | > ls PWSCF/ | ||
convergence_scripts input output psps | convergence_scripts input output psps | ||
In the <code>convergence_scripts</code> you will find some useful shell scripts to run the ground state convergence runs for Silicon. | In the <code>convergence_scripts</code> you will find some useful shell scripts to run the ground state convergence runs for Silicon. | ||
The YAMBO folder contains the Yambo input/output files and core databases. | The YAMBO folder contains the Yambo input/output files and core databases. | ||
> ls YAMBO/ | > ls YAMBO/ | ||
2x2x2/ 4x4x4/ 6x6x6/ 8x8x8/ Convergence_Plots_and_Scripts/ GAMMA/ | 2x2x2/ 4x4x4/ 6x6x6/ 8x8x8/ Convergence_Plots_and_Scripts/ GAMMA/ | ||
| Line 42: | Line 36: | ||
The core databases are provided for several k-points grids. In addition the folder <code>Convergence_Plots_and_Scripts</code> contains some scripts used for the [Silicon|GW tutorial] . | The core databases are provided for several k-points grids. In addition the folder <code>Convergence_Plots_and_Scripts</code> contains some scripts used for the [Silicon|GW tutorial] . | ||
Here we will just use the 8x8x8 (which is still very far from convergence) folder for computing (nonequilibrium) optical properties. | Here we will just use the 8x8x8 (which is still very far from convergence) folder for computing (nonequilibrium) optical properties. | ||
To run the tutorial you will need the standard executables | |||
yambo | |||
ypp | |||
plus the executables of the real time module of the Yambo code | |||
yambo_rt | |||
ypp_rt | |||
= Equilibrium optical properties = | |||
Enter the folder 8x8x8 | |||
> cd 8x8x8 | |||
For this step you can either compute static screening at equilibrium, or use the screening computed for the GW step in the Bethe-Salpeter | |||
== Static screening at equilibrium == | |||
== Solving the Bethe-Salpeter equation == | |||
= Generating non-equilibrium carriers = | |||
= Energy shift in the band structure = | |||
== COHSEX corrections at equilibrium == | |||
== Screening in presence of non-equilibrium carriers == | |||
== COHSEX corrections in presence of non-equilibrium carriers == | |||
= Renormalization of the exciton binding energy = | |||
Revision as of 13:37, 13 November 2024
In this tutorial you will learn the basic concepts for computing changes in the optical properties of a semi-conductor in presence of a non-equilibrium electrons and holes distribution in conduction and valence band respectively. This tutorial is based on the results published in Phys. Rev. B[1]
Under construction
The material: Silicon
We will study nonequilibrium absorption in bulk silicon. The same material used for this [Silicon|GW tutorial]
- FCC lattice
- Two atoms per cell (8 electrons)
- Lattice constant 10.183 [a.u.]
- Plane waves cutoff 15 Rydberg
- Direct gap 3.4 eV at Gamma
- Indirect gap 1.1 eV between Gamma= (0 0 0) and a point X', close to X=(0 1 0)
Tutorial files and Tutorial structure
Follow the instructions in Tutorials#Files and download/unpack the Silicon.tar.gz.
Once the tutorial archive file is unzipped the following folder structure will appear
COPYING README Silicon/
with the Solid_Si folder containing
> ls Silicon/ PWSCF/ YAMBO/
In the Pwscf folder the student will find an input/output directory with input/output files for pw.x. The Silicon pseudopotential file is also provided.
> ls PWSCF/ convergence_scripts input output psps
In the convergence_scripts you will find some useful shell scripts to run the ground state convergence runs for Silicon.
The YAMBO folder contains the Yambo input/output files and core databases.
> ls YAMBO/ 2x2x2/ 4x4x4/ 6x6x6/ 8x8x8/ Convergence_Plots_and_Scripts/ GAMMA/
The core databases are provided for several k-points grids. In addition the folder Convergence_Plots_and_Scripts contains some scripts used for the [Silicon|GW tutorial] .
Here we will just use the 8x8x8 (which is still very far from convergence) folder for computing (nonequilibrium) optical properties.
To run the tutorial you will need the standard executables
yambo ypp
plus the executables of the real time module of the Yambo code
yambo_rt ypp_rt
Equilibrium optical properties
Enter the folder 8x8x8
> cd 8x8x8
For this step you can either compute static screening at equilibrium, or use the screening computed for the GW step in the Bethe-Salpeter