Computer Lab: Difference between revisions

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==JUPYTER notebooks==
==JUPYTER notebooks==
* [[Media:Getting_started_python.ipynb.txt|Getting started with Python]]
* [[Media:Getting_started_python.ipynb.txt|Getting started with Python]]
* [[Media:getting_started_numpy_and_scipy.ipynb|Getting started with NumPy and SciPy]]
* [[Media:Getting_started_numpy_and_scipy.ipynb.txt|Getting started with NumPy and SciPy]]
* [[Media:getting_started_matplotlib.ipynb|Getting started with Matplotlib]]
* [[Media:getting_started_matplotlib.ipynb|Getting started with Matplotlib]]
* [[Media:xyz.ipynb|Nanostructures in equilibrium with Python]]
* [[Media:xyz.ipynb|Nanostructures in equilibrium with Python]]

Revision as of 11:48, 2 September 2020

Installing Python and course related packages

  • Install Anaconda
  • If you want to add RISE package for Jupyter notebooks, execute:
conda install -c conda-forge rise
conda install -c conda-forge kwant
pip install pythtb --upgrade
pip install --upgrade --user ase
python -m ase test

JUPYTER notebooks

Python references

KWANT references

Density functional theory with GPAW package

How to run GPAW on ulam

GPAW has been installed on ulam with the OS installed python 2.6.

  • in order to use the serial version of GPAW type:
 python your_gpaw_program.py
  • in order to use the parallel version of gpaw use the following syntax (replace 8 with the number of cores you want to use):
 mpirun -np 8 gpaw-python_openmpi your_gpaw_program.py

Getting started with GPAW

from ase import Atoms
from ase.io import write
from ase.optimize import QuasiNewton
from gpaw import GPAW

d = 1.10  # Starting guess for the bond length
atoms = Atoms('CO', positions=((0, 0, 0),
                               (0, 0, d)), pbc=False)
atoms.center(vacuum=4.0)
write('CO.cif', atoms)
calc = GPAW(h=0.20, xc='PBE', txt='CO_relax.txt')
atoms.set_calculator(calc)

relax = QuasiNewton(atoms, trajectory='CO.traj', logfile='qn.log')
relax.run(fmax=0.05)

GPAW Exercises Related to Midterm Project

References

First-principles quantum transport calculations using NEGF+DFT within GPAW package

Theory Background

  • Crash course on NEGF+DFT codes
  • NEGF+DFT within GPAW - see also J. Chen, K. S. Thygesen, and K. W. Jacobsen, Ab initio nonequilibrium quantum transport and forces with the real-space projector augmented wave method, Phys. Rev. B 85, 155140 (2012). [PDF]
  • M. Strange, I. S. Kristensen, K. S. Thygesen, and K. W. Jacobsen, Benchmark density functional theory calculations for nanoscale conductance, J. Chem. Phys. 128, 114714 (2008). [PDF]
  • D. A. Areshkin and B. K. Nikolić, Electron density and transport in top-gated graphene nanoribbon devices: First-principles Green function algorithms for systems containing a large number of atoms, Phys. Rev. B 81, 155450 (2010). [PDF]

GPAW Exercises