In paramagnetic materials, the density of states for spin up and spin down electrons are the same. So there is no spin polarization.
In ferromagnetic materials, their DOS are different. So, they are spin polarized. One is majority and the other is minority carrier.
In half-metallic...
Oh sorry for posting the stupid question about how to "track" eigen numbers. I kind of been able to reproduce some of Nakada et al. results. Thanks for all you guys, especially saaskis, for your kind help. Though my results for small number of atoms are not in good agreement with Nakada et al...
Yeah, that's true. I found all the eigenvalues for one value of k. So, if I have intersecting subbands, when I sweep the value of the k, how do I keep track of the corresponding eigen values of different subbands?
For some reason the above post doesn't have the last row of the beta matrix which is:
0.0 0.0 0.0 0.0 2.0 0.0 0.0 0.0
So, the total form of the beta matrix is :
beta.dat :
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0...
Hi all,
I encountered a problem while running a FORTRAN 90 program, which appears (to me) to be quite surprising. Can someone please explain the following things:
1. Why the (4,1) element of the beta matrix is 5.0 instead of being 2.0 ??
2. Why the (5,8) element of the beta matrix...
Hey, thank you for being so helpful. Now I understand the physics, but have a couple of questions about the computation.
1. If I take N=50, for each k-value within the first Brillouin zone, I have to diagonalize the 2N*2N matrix. I have a 1.6GHz processor with 1Gb RAM and 100Gb...
I'm still in the process of "just getting started" :). But I read in some relatively unreliable sources, that based on k.p approximation low energy excitons obey the 2D Dirac-like equation. But I'm not quite sure whether based on this, one can establish similarities between results of TB...
Yes,Nakada et al did TB calculation. I gave it as a reference because both TB calclation and Dirac equation solution gives similar results, but in the "high energy" limit.
Yes I'm new to TB calculations. I'll definitely look at the book. Thank you so much.
I'm thinking of doing the band structure calculation by solving the Dirac equation for graphene nanoribbons. I want to show that there are "edge states" for zigzag and no such thing exists for armchair.
This can be done analytically. I'm confused about the scope of computation in this case. Do...
Hey
First of all,thank you so much for the reply. It'll be a good idea to take the magnetic field into the hopping Hamiltonian. But, I don't understand why do you think there will be enough programing without the magnetic field. I did it analytically as a undergrad couple of years back, and...
I'm taking a graduate course on computational physics which has a project. I'm doing research
on electronic properties of graphene, like quantum hall effect measurements. So, I want to do the project related to my research.
The project shouldn't be too difficult, as I haven't done simulations...