Valence and conduction bands in five band Hamiltonian

[Mohammad-gl]

Hello,
I have this band structure plot for five band Hamiltonian model. I want to know which bands are valence and which one is conduction bands. Also if they have any special name I like to know that.
Thank you.

 

[bob012345]

Hello,
I have this band structure plot for five band Hamiltonian model. I want to know which bands are valence and which one is conduction bands. Also if they have any special name I like to know that.
Thank you.

Usually, if the energy is above ##0 eV## it is the conduction band, if below it is the Valence band. The confusing part of this diagram is that it looks like the material changes from insulator to semi-conductor to metal and back as you go from left to right. What is the material?

 

[Mohammad-gl]

Usually, if the energy is above ##0 eV## it is the conduction band, if below it is the Valence band. The confusing part of this diagram is that it looks like the material changes from insulator to semi-conductor to metal and back as you go from left to right. What is the material?

this is b12-borophene material

 

[bob012345]

this is b12-borophene material

Here is a reference to that material which has the band diagram color coded on page 5.

https://www.researchgate.net/publication/342185652_Two-Dimensional_Borophene_Properties_Fabrication_and_Promising_Applications/download

 

[Mohammad-gl]

Here is a reference to that material which has the band diagram color coded on page 5.

https://www.researchgate.net/publication/342185652_Two-Dimensional_Borophene_Properties_Fabrication_and_Promising_Applications/download

Thank you

 

[bob012345]

Based on these references and some more thought, I now think this band diagram shows this material is a metal but the overlapping bandgap is indirect for certain directions and direct for other directions.

This is Borophene specific;
"First-Principles Investigation of Borophene as a Monolayer Transparent Conductor "
https://www.osti.gov/pages/servlets/purl/1467636

This is a Nature review article;
"Bandgap engineering of two-dimensional semiconductor materials" https://www.nature.com/articles/s41699-020-00162-4.pdf