QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Dipankar Saha on April 27, 2015, 15:07

Title: 2D plot of hexagonal surface Brillouin zone
Post by: Dipankar Saha on April 27, 2015, 15:07

How can I get .... a 2D plot of  hexagonal surface Brillouin zone  (projection along, kx-ky)....such that the equivalent Fermi surface pockets ( say, at K-K' ) can be determined ??   :)

Regards__
Dipankar

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Anders Blom on April 27, 2015, 15:43

Try these

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Dipankar Saha on April 27, 2015, 18:38

Thank u.....  :)  / But the 'graphene.py' does not have any band struct. analysis..... So, I was getting an error.....

Traceback (most recent call last):
  File "/home/dipankar/Desktop/cb_plot.py", line 7, in <module>
    bs = nlread('graphene.nc', Bandstructure)[-1]
IndexError: list index out of range
Traceback (most recent call last):
  File "/home/dipankar/Desktop/cb_plot.py", line 7, in <module>
    bs = nlread('graphene.nc', Bandstructure)[-1]
_____________________



Next, I include the following lines in 'graphene.py' .....

bandstructure = Bandstructure(
    configuration=bulk_configuration,
    route=['G', 'M', 'K', 'G'],
    points_per_segment=201,
    bands_above_fermi_level=All
    )
nlsave('graphene.nc', bandstructure)



Then the warning message,  while running  'cb_plot.py',  shows____

/usr/local/QuantumWise_14_2/VNL-ATK-2014.2/lib/python2.7/site-packages/matplotlib/delaunay/triangulate.py:103: DuplicatePointWarning: Input data contains duplicate x,y points; some values are ignored.
/usr/local/QuantumWise_14_2/VNL-ATK-2014.2/lib/python2.7/site-packages/matplotlib/delaunay/triangulate.py:103: DuplicatePointWarning: Input data contains duplicate x,y points; some values are ignored.
/usr/local/QuantumWise_14_2/VNL-ATK-2014.2/lib/python2.7/site-packages/matplotlib/delaunay/triangulate.py:103: DuplicatePointWarning: Input data contains duplicate x,y points; some values are ignored.
__________

Hence___ 
the file 'cb_plot.py' is not generating the 2D hex. surface BZ  !!!  :-\

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Anders Blom on April 27, 2015, 22:32

Sorry, was missing one file.
Run this after the main calculation, before the plot script.

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Dipankar Saha on April 28, 2015, 08:39

Thank you  very much Anders....  :) ....Now, it's fine !!!

Can we impose the 2D BZ lines on this contour plots? 
 Besides, for this specific case ...... the color bar is showing a range  about  -0.3 to -6.5 , for both the cb_plot and vb_plots.
 -0.3 relates to high?? For both vb_max, cb_min .... will the sign be negative??

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Anders Blom on April 28, 2015, 15:21

No, the output shows +0.3 to +6.5 for CB, unless you modified something the wrong way :)

BZ added - see new script (renamed). Plot style is controlled on 52, you can change color and width of the BZ line (blue and width 2 now).

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Anders Blom on April 28, 2015, 15:22

And valence band

Title: Re: 2D plot of hexagonal surface Brillouin zone
Post by: Dipankar Saha on April 28, 2015, 15:52

Awesome...!!!!  / This is something... that I was looking for...... :)

Yes, It was my fault.... Actually  the 'zi'  variable was getting overwritten..../

Thanks again...!!!  :)

Regards__
Dipankar