Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

2D dirac equation for graphene

Please login with a confirmed email address before reporting spam

Hi,

I am trying to simulate graphene using Dirac equation in 2D. First, I wanted to try something simple like free particle and particle in a box using Dirac equation (rather than Schrodinger equation). I used PDE modes -> PDE, Coefficient Form -> Eigenvalue analysis. I put 'u1 u2' as the dependent variables and enter the coefficient as in the Dirac equation. For boundary condition, I specified 'u' to be zero at the boundaries (particle in a box).

However, the result that I got indicate the energy level (eigenvalues) as complex numbers and the wavefunctions spread out to the edge as attached (not form a standing wave pattern as expected).

I don't know what wrong with the model. Note that, I tried with Schrodinger equation and it works. So, the differences are only the equations in subdomain.

Any idea will be much appreciated. Thank you in advance.

Sansiri


1 Reply Last Post Feb 25, 2011, 8:02 a.m. EST
COMSOL Moderator

Hello Sansiri

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.


Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Feb 25, 2011, 8:02 a.m. EST
Dear Sansiri,

Did you managed to get your model working? If not you could try upload your model file, this would make it a lot easier to find problems with your model and try and solve them.

Best Wishes

Daniel
Dear Sansiri, Did you managed to get your model working? If not you could try upload your model file, this would make it a lot easier to find problems with your model and try and solve them. Best Wishes Daniel

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.