Re: [Kwant] ensuring Hermitian hopping

5 May 2016


      On 05/05/16 21:53, Anton Akhmerov wrote:
...
Hi Sergey,
...
Builder instances automatically ensure that every hopping is Hermitian, so that if builder[a, b] has been set, there is no need to set builder[b, a].
So you don't need to pay any extra effort to ensure hermiticity.
However your code has a different minor drawback. The order in which
Quoting from http://kwant-project.org/doc/1/reference/generated/kwant.builder.Builder#kwa...:
the hoppings are evaluated in Kwant is not deterministic, so you will
get random results that you are unable to reevaluate. You could avoid
this by using the hash-based random number generators provided by
kwant.digest. See e.g. code here for an example of use
http://arxiv.org/src/1408.1563v2/anc/trijunction.py (the "disorder"
function).
Best,
Anton
On Thu, May 5, 2016 at 9:48 PM, Sergey  wrote:
...
Dear all,
   I want to model a random variation of hopping integrals.  Simply writing:
def hopping(sitei, sitej):
     return -1 + random.gauss(0,0.2)
does not work  since this does not ensure that the hopping is Hermitian.
Is there a smart way to write something like:
def hopping(sitei, sitej):
     if sitei
?
Thanks and best wishes,
Sergey