joselado/pyqula

Python library to compute different properties of quantum tight binding models in a lattice

pyqula's Issues

define onsites and hoppings

Hi dear Joselado,
I have some questions:
I want to make a 3*3 graphene supercell (how can I do that?)
And then I want to define different values for onsite of each atom, for example I have a list of numbers for onsite values and I want to make my own hamiltonian with those numbers.
Could you please help me?
Best regards

How to plot 2d band structure and contour plot?

Dear Joselado,
Please help me to plot 2d band structure for graphene and other materials, in which energy plotted with kx and ky. and I need also to have its contour plot.
Thank you
Best regards, Masoumeh

3d band structure for graphene and other materials

Hi,
Thank you for your response to my previous questions. I want to plot 3d band structure like the attached figure and its contour plot. I am be appreciated with your help.

Best regards

Docs?

Hi! Just skimmed a bit through the code, installed it and played a bit with some basic usage. Everything feels quite interesting and well packed, at least in terms of great usability and fast workflow. But I could not find even a minimal attempt of documentation or schematic README files. I fear it would be a nightmare to jump on-board and make a good use of it if I have not a clear resource on what the package can really do, a minimal tree map of the classes and methods, and so forth. I feel like I can't really get how to pass my custom parameters to get_hamiltonian() without a listing of the **kwargs :)
The examples folder seems to not suffice, for it's more a full database of test cases, than a commented tutorial in steps. And one has no idea if every possibility is covered and where to find an implementation for it.
Still I don't want to resort to quantum-honeycomp since I intend to integrate the TB model-building and solution as an upstream source for subsequent computation, so flexibility and transparency is paramount.
I'm quite sad since I really feel like this package provides far more content than the infamous PythTB and I seriously considered to hop here (:

Have you maybe some external resource (like lecture notes for some hands-on course at your department, or some workshop elsewhere)? Can we expect in a short to mid term some sort of docs?

How to do calculations for other structures?

Hi dear Joselado,
Thank you for your excellent package. I want to add my own structure for example cif or xyz file. Can I import these files and calculate band structure and do other available computations?
Best regards
Masoumeh Alihosseini
Postdoc in physics

Impurities / Documentation

Hello, I'd first like to congratulate on your outstanding work. My MSc thesis concerned topological superconductors, and even though I've now moved on to Machine Learning in the industry, I still play around with physics whenever I have the time. This is how I found this repo and all I can say is that your open source work is remarkable.

First of all, I would like to ask if there is any way to help you with documentation about this huge project. Someone more experienced with code and theory may manage to find what they're looking for, but I fear that pre- or even post-graduate students may find some difficulty navigating, which is a shame since your code has a lot to offer them, both educationally and research-wise.

Secondly, I have a more specific question: I was wondering if you have created systematic ways to play around with impurities. I've seen some examples where you add a single impurity using the embedding class, however I haven't seen a more "organized" way to define impurities. For example, how would one go about defining a slab and then placing on top of it a chain of impurities with certain spin configurations (for example forming a helix)? Do you think this is something that can be done with the code as it is now, or do such examples require it to be expanded first?

Once again, thank you for your remarkable contribution. I'd be glad to be of any help, either with documentation, or with questions such as the aforementioned one. Keep it up and best of luck!

How to derive the simplified formula in berry_green_generator

Hi joselado,

Thank you for your awesome work. I learned a lot from it.

Just one thing I didn't get, a simplified formula in berry_green_generator. The line below which you commented out seems to be the original formula and is consistent with the valley flux formula in this paper .

Would you mind enlighting me on how to derive the simplified formula or throwing some relevant links/keywords?