Plot BSE fatbands - Revision history

Tal at 09:14, 26 October 2023

2023-10-26T09:14:12Z

← Older revision		Revision as of 09:14, 26 October 2023
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	It can be useful to inspect which electron-hole pairs contribute the most to a particular ~~BSE eigenvector~~ {{cite\|bokdam:scr:2016}}. In VASP it is possible to write the lowest {{TAG\|NBSEEIG}} eigenvectors into the {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.		It can be useful to inspect which electron-hole pairs or transitions contribute the most to a particular exciton {{cite\|bokdam:scr:2016}}. In VASP it is possible to write the lowest {{TAG\|NBSEEIG}} eigenvectors into the {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.

	For example, a fatband structure plot for the first bright exciton can be made following these steps:		For example, a fatband structure plot for the first bright exciton can be made following these steps:

Tal: Tal moved page Plot BSE fatband to Plot BSE fatbands

2023-10-26T09:04:52Z

Tal moved page Plot BSE fatband to Plot BSE fatbands

← Older revision	Revision as of 09:04, 26 October 2023
(No difference)

Tal: Tal moved page Plotting the BSE fatband structure to Plot BSE fatband

2023-10-26T09:04:07Z

Tal moved page Plotting the BSE fatband structure to Plot BSE fatband

← Older revision	Revision as of 09:04, 26 October 2023
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Tal: Tal moved page Construction:Plotting the BSE fatband structure to Plotting the BSE fatband structure

2023-10-16T16:33:09Z

Tal moved page Construction:Plotting the BSE fatband structure to Plotting the BSE fatband structure

← Older revision	Revision as of 16:33, 16 October 2023
(No difference)

Tal at 16:45, 20 July 2022

2022-07-20T16:45:18Z

← Older revision		Revision as of 16:45, 20 July 2022
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	# Plot the band structure with point size corresponding to the coupling coefficients Abs(X_BSE), i.e.,		# Plot the band structure with point size corresponding to the coupling coefficients Abs(X_BSE), i.e.,

	\|k-point\| electron ~~hole~~ Abs(X_BSE)		\|k-point\| hole electron Abs(X_BSE)
	eigenvalue eigenvalue		eigenvalue eigenvalue
	x y1 y2 circle radius		x y1 y2 circle radius

Tal at 16:39, 20 July 2022

2022-07-20T16:39:41Z

← Older revision		Revision as of 16:39, 20 July 2022
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	awk < BSE-$NBSE.dat '{ if ($1==$3 && $2==0.0) print sqrt($1$1+$2$2+$3*$3), $4, $5, $6}' > bands-GX.dat		awk < BSE-$NBSE.dat '{ if ($1==$3 && $2==0.0) print sqrt($1$1+$2$2+$3*$3), $4, $5, $6}' > bands-GX.dat

	[[File:Bsefatband.png\|300px\|thumb\|The fatband structure plot ~~of a~~ BSE ~~eigenvector~~ in Si]]		[[File:Bsefatband.png\|300px\|thumb\|The fatband structure plot for one the BSE eigenvectors in Si]]

	The fatband structure plot can be done in gnuplot by running the following script:		The fatband structure plot can be done in gnuplot by running the following script:
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	== Related tags and sections ==		== Related tags and sections ==
	{{FILE\|BSEFATBAND}}, {{FILE\|NBSEEIG}}, [[Bethe-Salpeter-equations calculations\|BSE]]		{{FILE\|BSEFATBAND}}, {{FILE\|NBSEEIG}}, [[Bethe-Salpeter-equations calculations\|BSE]]

	== References ==		== References ==
	~~<references/>~~

	[[Category:VASP]][[Category:Many-body perturbation theory]][[Category:Bethe-Salpeter equations]]		[[Category:VASP]][[Category:Many-body perturbation theory]][[Category:Bethe-Salpeter equations]]

Tal at 16:36, 20 July 2022

2022-07-20T16:36:15Z

← Older revision		Revision as of 16:36, 20 July 2022
Line 1:		Line 1:
	It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the lowest {{TAG\|NBSEEIG}} eigenvectors into a {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.		It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector {{cite\|bokdam:scr:2016}}. In VASP it is possible to write the lowest {{TAG\|NBSEEIG}} eigenvectors into the {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.

	For example, a fatband structure plot for the first bright exciton can be made following these steps:		For example, a fatband structure plot for the first bright exciton can be made following these steps:
	# Perform a [[Bethe-Salpeter-equations calculations\|BSE]] calculation with {{TAG\|NBSEEIG}} sufficiently large to include the exciton of interest.		# Perform a [[Bethe-Salpeter-equations calculations\|BSE]] calculation with {{TAG\|NBSEEIG}} sufficiently large to include the exciton of interest.
	# Find the energy of the first bright exciton in {{FILE\|vasprun.xml}} (''<varray name="opticaltransitions" >'')		# Find the energy of the first bright exciton in {{FILE\|vasprun.xml}}, i.e., the first transition with non-zero oscillator strength (''<varray name="opticaltransitions" >'')
	# Find the BSE eigenvector corresponding to this transition in the {{FILE\|BSEFATBAND}} file.		# Find the BSE eigenvector corresponding to this transition in the {{FILE\|BSEFATBAND}} file.
	# Extract the coupling coefficients ''Abs(X_BSE)'' (Column 6) and energies (Column 4 and 5) corresponding to k points (Columns 1-3) along high-symmetry paths.		# Extract the coupling coefficients ''Abs(X_BSE)'' (Column 6) and energies (Column 4 and 5) corresponding to k points (Columns 1-3) along high-symmetry paths.
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	awk < BSE-$NBSE.dat '{ if ($1==$3 && $2==0.0) print sqrt($1$1+$2$2+$3*$3), $4, $5, $6}' > bands-GX.dat		awk < BSE-$NBSE.dat '{ if ($1==$3 && $2==0.0) print sqrt($1$1+$2$2+$3*$3), $4, $5, $6}' > bands-GX.dat

			[[File:Bsefatband.png\|300px\|thumb\|The fatband structure plot of a BSE eigenvector in Si]]

	The fatband structure plot can be ~~produced~~ in gnuplot by running the script:		The fatband structure plot can be done in gnuplot by running the following script:

	set size 0.5,1		set size 0.5,1
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	set xrange[-0.866025:0.707107]		set xrange[-0.866025:0.707107]
	M=0.001		M=0.001
	p "bands-GL.dat" u (-$1):2:(M*($4)) w circles lc rgb "#2C68FC", \
			p "bands-GL.dat" u (-$1):2:(M*($4)) w circles lc rgb "#2C68FC", \
	"" u (-$1):3:(M*($4)) w circles lc rgb "#A82C35", \		"" u (-$1):3:(M*($4)) w circles lc rgb "#A82C35", \
	"" u (-$1):2 ps 0.5 lc "#808080" w d, \		"" u (-$1):2 ps 0.5 lc "#808080" w d, \
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	[[~~File:Bsefatband.png~~\|~~500px\|caption~~=~~"ssdfsdf"~~]]		== Related tags and sections ==
			{{FILE\|BSEFATBAND}}, {{FILE\|NBSEEIG}}, [[Bethe-Salpeter-equations calculations\|BSE]]

			== References ==
			<references/>

			[[Category:VASP]][[Category:Many-body perturbation theory]][[Category:Bethe-Salpeter equations]]

Tal at 16:08, 20 July 2022

2022-07-20T16:08:15Z

← Older revision		Revision as of 16:08, 20 July 2022
Line 1:		Line 1:
	It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the ~~first~~ {{TAG\|NBSEEIG}} eigenvectors into a {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.		It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the lowest {{TAG\|NBSEEIG}} eigenvectors into a {{FILE\|BSEFATBAND}} file, which can be used for making a fatband structure plot.

	For example, a fatband structure plot for the first bright exciton can be made following these steps:		For example, a fatband structure plot for the first bright exciton can be made following these steps:
Line 47:		Line 47:


	[[File:Bsefatband.png\|500px]]		[[File:Bsefatband.png\|500px\|caption="ssdfsdf"]]

Tal at 16:00, 20 July 2022

2022-07-20T16:00:38Z

← Older revision		Revision as of 16:00, 20 July 2022
Line 36:		Line 36:
	M=0.001		M=0.001
	p "bands-GL.dat" u (-$1):2:(M*($4)) w circles lc rgb "#2C68FC", \		p "bands-GL.dat" u (-$1):2:(M*($4)) w circles lc rgb "#2C68FC", \
	"" u (-$1):3:(M*($4)) w circles lc rgb "#A82C35", \		"" u (-$1):3:(M*($4)) w circles lc rgb "#A82C35", \
	"bands-GX.dat" u 1:2:(M*($4)) w circles lc rgb "#2C68FC", \		"" u (-$1):2 ps 0.5 lc "#808080" w d, \
	"" u 1:3:(M*($4)) w circles lc rgb "#A82C35", \		"" u (-$1):3 ps 0.5 lc "#808080" w d, \
	"" u ~~(-$~~1):2 ps 0.5 ~~pt 4~~ lc "#808080" w p, \		"bands-GX.dat" u 1:2:(M*($4)) w circles lc rgb "#2C68FC", \
	"" u ~~(-$~~1):3 ps 0.5 ~~pt 4~~ lc "#808080" w ~~p, \~~		"" u 1:3:(M*($4)) w circles lc rgb "#A82C35", \
	~~"" u 1:2 ps 0.5 pt 4 lc "#808080" w p, \~~		"" u 1:2 ps 0.5 lc "#808080" w d, \
	~~"" u 1~~:~~3 ps 0~~.~~5 pt 4 lc "#808080" w p~~		"" u 1:3 ps 0.5 lc "#808080" w d




			[[File:Bsefatband.png\|500px]]

Tal: Created page with "It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the first {{TAG|NBSEEIG}} eigenvecto..."

2022-07-20T14:42:13Z

Created page with "It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the first {{TAG|NBSEEIG}} eigenvecto..."

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It can be useful to inspect which electron-hole pairs contribute the most to a particular BSE eigenvector. In VASP it is possible to write the first {{TAG|NBSEEIG}} eigenvectors into a {{FILE|BSEFATBAND}} file, which can be used for making a fatband structure plot.

For example, a fatband structure plot for the first bright exciton can be made following these steps:
# Perform a [[Bethe-Salpeter-equations calculations|BSE]] calculation with {{TAG|NBSEEIG}} sufficiently large to include the exciton of interest.
# Find the energy of the first bright exciton in {{FILE|vasprun.xml}} (''<varray name="opticaltransitions" >'')
# Find the BSE eigenvector corresponding to this transition in the {{FILE|BSEFATBAND}} file.
# Extract the coupling coefficients ''Abs(X_BSE)'' (Column 6) and energies (Column 4 and 5) corresponding to k points (Columns 1-3) along high-symmetry paths.
# Plot the band structure with point size corresponding to the coupling coefficients Abs(X_BSE), i.e.,

|k-point| electron hole Abs(X_BSE)
eigenvalue eigenvalue
x y1 y2 circle radius

You can use the following script for extracting the ''NBSE'' eigenvector along G-L and G-X directions in Si:

#!/bin/bash
#Select the BSE eigenvector of interest.
NBSE=1
# The BSE product basis size.
BSIZE=$(head -n 1 BSEFATBAND | awk '{print $1}')
i=`echo "($BSIZE+1)*$NBSE+1" | bc`
#Cut out the selected eigenstate.
head -n $i BSEFATBAND | tail -n $BSIZE > BSE-$NBSE.dat
awk < BSE-$NBSE.dat '{ if ($1==$2 && $3==$2) print sqrt($1*$1+$2*$2+$3*$3), $4, $5, $6}' > bands-GL.dat
awk < BSE-$NBSE.dat '{ if ($1==$3 && $2==0.0) print sqrt($1*$1+$2*$2+$3*$3), $4, $5, $6}' > bands-GX.dat

The fatband structure plot can be produced in gnuplot by running the script:

set size 0.5,1
set nokey
set ylabel "Energy (eV)"
set yrange[-7:21]
set xtics ("L" -0.866025, "Г" 0, "X" 0.707107)
set xrange[-0.866025:0.707107]
M=0.001
p "bands-GL.dat" u (-$1):2:(M*($4)) w circles lc rgb "#2C68FC", \
"" u (-$1):3:(M*($4)) w circles lc rgb "#A82C35", \
"bands-GX.dat" u 1:2:(M*($4)) w circles lc rgb "#2C68FC", \
"" u 1:3:(M*($4)) w circles lc rgb "#A82C35", \
"" u (-$1):2 ps 0.5 pt 4 lc "#808080" w p, \
"" u (-$1):3 ps 0.5 pt 4 lc "#808080" w p, \
"" u 1:2 ps 0.5 pt 4 lc "#808080" w p, \
"" u 1:3 ps 0.5 pt 4 lc "#808080" w p