Hi, my friends. Recently, I studied, on Kwant, the transport properties of a graphene nanoribbon without dificulty. Now, I wanted to obtain the same thing, but applying a strain, as suggested by this reference: http://arxiv.org/abs/1409.6666 In the presence strain, the hopping is modified by the deformation of the lattice, which must now be t_ij=t_0*exp(d/a - 1), where d is the strain-modified distance between lattice sites and t_0 is hopping in absence of strain. Note that the network is no longer crystalline. That way, I can not define the vectors of a single cell and repeat it to obtain my lattice. In this case, I guess I'll have to build every atom of the network and add the hopping according with the relation above to the nearest neighbors. Obviously, this not is good idea. Someone help me with a simpler solution? Thank you so much. Jonas Nascimento
Dear Jonas,
I believe a better solution for you would be to subclass the kwant
MonoatomicLattice, and replace its pos method that calculates the site
position with one that includes the lattice distortion.
Alternatively you can just not bother changing what Kwant knows about
the site positions, implement a function pos_transform(x, y) that
gives the coordinates of sites in the distorted lattice, and then
define hoppings similar to:
def hop(site1, site2, ...):
r1 = pos_transform(site1.pos)
r2 = pos_transform(site2.pos)
return f(r1 - r2)
Best,
Anton
On Fri, Oct 2, 2015 at 8:10 PM, Jonas Nascimento
Hi, my friends.
Recently, I studied, on Kwant, the transport properties of a graphene nanoribbon without dificulty. Now, I wanted to obtain the same thing, but applying a strain, as suggested by this reference: http://arxiv.org/abs/1409.6666
In the presence strain, the hopping is modified by the deformation of the lattice, which must now be
t_ij=t_0*exp(d/a - 1),
where d is the strain-modified distance between lattice sites and t_0 is hopping in absence of strain. Note that the network is no longer crystalline. That way, I can not define the vectors of a single cell and repeat it to obtain my lattice. In this case, I guess I'll have to build every atom of the network and add the hopping according with the relation above to the nearest neighbors. Obviously, this not is good idea. Someone help me with a simpler solution?
Thank you so much.
Jonas Nascimento
participants (2)
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Anton Akhmerov
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Jonas Nascimento