Bosonic Haldane Model
Posted: 20 Aug 2020, 22:48
I am going through some example models, and was looking at the Bosonic Haldane Model in particular:
https://github.com/tenpy/tenpy/blob/mas ... py#L13-L80
It is stated that the Hamiltonian reads
Is this code double-summing? I mean, the for-loop runs over u=0,1 of the honeycomb, and seems to repeat the same action in each pass. So it feels like it is implementing \sum_i 2\mu (n_{A,i} - n_{B,i}). Or, am I mistaken and not understanding its action correctly at all?
https://github.com/tenpy/tenpy/blob/mas ... py#L13-L80
It is stated that the Hamiltonian reads
However, looking at the implementation of on-site terms I see.. math ::
H = \sum_{ij} t_{ij} b_i^\dagger b_j + \sum_i \mu (n_{A, i} - n_{B, i})
+ V \sum_{\langle ij \rangle, i<j} n_{A, i} n_{B, j}
Code: Select all
for u in range(len(self.lat.unit_cell)):
self.add_onsite(mu, 0, 'N', category='mu N')
self.add_onsite(-mu, 1, 'N', category='mu N')