Distinguish contribution from different valleys
Hello everyone, I’m studying valley currents in graphene monolayers and I would like to distinguish the contribution to the transmission matrix elements and to the wavefunctions from different valleys. Until now the only idea I have had is inspired by a work made by Beenakker et al. in 2007 where, in a graphene ribbon with only zig-zag edges, they attribute the modes with longitudinal wavevector in (pi,2pi) to the first valley, whereas the modes with longitudinal wavevector in (0,pi) to the second valley. To apply this method I would need to know how kwant orders the elements of the scattering matrix. Anyway, the idea that I have exposed only partly solves my problem because the system I have in mind has both zig-zag and armchair edges. Someone could suggest a way to do that? Thanks for the attention! Best, Michael
Hi Michael, What you want should be relatively straightforward to implement. * The scattering matrix contains a lead_info attribute (http://kwant-project.org/doc/1.0/reference/generated/kwant.solvers.common.SM...) * The lead_info contains mode wave functions, their momenta and velocities. Their sort order is explained over here: http://kwant-project.org/doc/1.0/reference/generated/kwant.physics.Propagati... Please share your code if you figure out a way: the questions about modes are common, and a nice example would be extremely useful. Best, Anton On Tue, Oct 13, 2015 at 10:49 PM, Michael Beconcini <dottus@gmail.com> wrote:
Hello everyone,
I’m studying valley currents in graphene monolayers and I would like to distinguish the contribution to the transmission matrix elements and to the wavefunctions from different valleys.
Until now the only idea I have had is inspired by a work made by Beenakker et al. in 2007 where, in a graphene ribbon with only zig-zag edges, they attribute the modes with longitudinal wavevector in (pi,2pi) to the first valley, whereas the modes with longitudinal wavevector in (0,pi) to the second valley. To apply this method I would need to know how kwant orders the elements of the scattering matrix.
Anyway, the idea that I have exposed only partly solves my problem because the system I have in mind has both zig-zag and armchair edges. Someone could suggest a way to do that?
Thanks for the attention!
Best, Michael
Thank you for the help: now I have understood how to use these tools of want. Anyway I have still to think on how to figure out a way for what I want to do, so I don’t have any code to share a t the moment. Thanks again, Michael
Il giorno 13 ott 2015, alle ore 15:54, Anton Akhmerov <anton.akhmerov@gmail.com> ha scritto:
Hi Michael,
What you want should be relatively straightforward to implement. * The scattering matrix contains a lead_info attribute (http://kwant-project.org/doc/1.0/reference/generated/kwant.solvers.common.SM...) * The lead_info contains mode wave functions, their momenta and velocities. Their sort order is explained over here: http://kwant-project.org/doc/1.0/reference/generated/kwant.physics.Propagati...
Please share your code if you figure out a way: the questions about modes are common, and a nice example would be extremely useful.
Best, Anton
On Tue, Oct 13, 2015 at 10:49 PM, Michael Beconcini <dottus@gmail.com> wrote:
Hello everyone,
I’m studying valley currents in graphene monolayers and I would like to distinguish the contribution to the transmission matrix elements and to the wavefunctions from different valleys.
Until now the only idea I have had is inspired by a work made by Beenakker et al. in 2007 where, in a graphene ribbon with only zig-zag edges, they attribute the modes with longitudinal wavevector in (pi,2pi) to the first valley, whereas the modes with longitudinal wavevector in (0,pi) to the second valley. To apply this method I would need to know how kwant orders the elements of the scattering matrix.
Anyway, the idea that I have exposed only partly solves my problem because the system I have in mind has both zig-zag and armchair edges. Someone could suggest a way to do that?
Thanks for the attention!
Best, Michael
participants (2)
-
Anton Akhmerov -
Michael Beconcini