Charge density distribution

[bfazi]

Hello,

Can anyone help me to interpret my results about charge density distribution and opening bandgap in silicene nanoribbon? I applied a compressive strain to a silicene nanoribbon and results show that the bandgap of the ribbon increases by applying compressive strain. To understand the reason of this issue, I obtained the charge density distribution of the ribbon before and after applying strain by calculation of Blochstate. I attache my results to this post. Please help me to interpret my results.

Many Thanks

[zh]

The simple use of charge density couldn't give any hint to understand the band gap opening in silicene nanorbbion.  You can read the following papers to understand how the strain affect the electronic structure of graphene and how the band gap is formed in silience nanoribbon:
http://journals.aps.org/prb/abstract/10.1103/PhysRevB.81.241412
http://scitation.aip.org/content/aip/journal/jap/118/10/10.1063/1.4930139
http://scitation.aip.org/content/aip/journal/adva/2/2/10.1063/1.4732134
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.102.236804

From these papers, you may get some hints to understand the effect of strain the electronic structure of silience nanoribbon.

I guess you are a scientist researcher.  It is not a good style to post your the results of your scientific research and then ask other people to explain them.

 

[GJK]

Dear Azi,

With respect to your study I could find that you have a phase change at the valence band in the unstrained and strained material but there is no phase change at the conduction band(just see the colour bar).The phase change in the charge density plot should be the reason for opening the band gap in the material.Just refer this paper it will be apt to your studies I  think.
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4946362

But you need to find what kind of phase transformation it is(like anatase or rutile etc?I don't know how to find phase transformation using atk.

Thank you.

[zh]

The partial charge density (i.e., the square of Bloch state for some specific energy states) may tell us the orbital shape information (i.e., the orbital component). But is still far to understand the band gap opening.

To understand the band gap formation, at least the orbital components in the bonding states and anti-bonding states, the orbital interaction strength at a given atomic structure.