Hi!
I am a degree physics student and I am learning to use tenpy, sorry if the question is very basic.
I am trying to implement the t-J model in a chain
\(\hat{H}=-t \sum_{\langle i j\rangle, \sigma}\left(a_{i \sigma}^{\dagger} a_{j \sigma}+\mathrm{h.c.}\right)+\frac{1}{2} J \sum_{\langle i j\rangle}\left(\vec{S}_{i} \cdot \vec{S}_{j}-\frac{n_{i} n_{j}}{4}\right)\)
however I get an error when I try to construct a hamiltonian with c and cdag operators and spin operators mixed.
How could I implement it?
Thanks for reading me !
Implementation of t-J model
Re: Implementation of t-J model
Hi Leandro,
From my understanding, you may need to define your own sites before constructing the model Hamiltonian as the t-J site is not pre-defined in TeNPy, so something like:
Then you can use for example the CouplingMPOModel class to define the model Hamiltonian:
Hope this can help you!
Best,
Yixuan
From my understanding, you may need to define your own sites before constructing the model Hamiltonian as the t-J site is not pre-defined in TeNPy, so something like:
Code: Select all
class tJSite(Site):
def __init__(self, conserve='Sz'):
(define conserve quantity, operators, local site degree of freedom, etc)
def __repr__(self):
(debug?)
Code: Select all
class tJ(CouplingMPOModel):
def __init__(self, model_params):
CouplingMPOModel.__init__(self, model_params)
def init_sites(self, model_params):
return tJSite(conserve)
def init_terms(self, model_params):
(define terms)
Best,
Yixuan
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- Posts: 2
- Joined: 20 Mar 2021, 20:40
Re: Implementation of t-J model
Hi!,
You're right, I'm going to try to do it.
Thank you very much Yixuan!
You're right, I'm going to try to do it.
Thank you very much Yixuan!
Re: Implementation of t-J model
Hi Leandro,
apologies for not replying earlier!
Just to check: Did this work out, did you manage it in the end? Or do you still need help? I hope you didn't give up!
The t-J model is definitely sufficiently important/generic that it would be a good idea to include it into TeNPy itself.
Would you like to contribute that? I can give you further pointers how to do it / help with the implementation if necessary.
Best,
Johannes
apologies for not replying earlier!
Just to check: Did this work out, did you manage it in the end? Or do you still need help? I hope you didn't give up!
The t-J model is definitely sufficiently important/generic that it would be a good idea to include it into TeNPy itself.
Would you like to contribute that? I can give you further pointers how to do it / help with the implementation if necessary.
Best,
Johannes