Messages

1

General Questions and Answers / REMOTE ACCESS

« on: September 13, 2012, 12:18 »

I HAVE LICENSED ATK 12.2.2 INSTALLED IN REDHAT LINUX...
I WANT TO REMOTELY ACCESS THIS COMPUTER BY ANOTHER COMPUTER WHICH ALSO HAS REDHAT OS..
DOES THIS REQUIRE ANY SOFTWARE FEASIBILITY...
PLZ SUGGEST THE STEPS TO DO SO...

THANKING YOU BEFOREHAND..

2

General Questions and Answers / Re: bulkjunction script used as nanoribbon

« on: July 27, 2012, 08:33 »

atk 12.2.1

3

General Questions and Answers / Re: bulkjunction script used as nanoribbon

« on: July 25, 2012, 13:31 »

i want to build Au/armchair/Au two probe device...i have made armchair nano ribbon in the builder but
i am unable to create the Gold electrodes and interface it with the nanoribbon channel..
can you please help..

4

General Questions and Answers / bulkjunction script used as nanoribbon

« on: July 25, 2012, 11:43 »

can bulkjunction.py script be used for naoribbon as a channel

5

Installation and License Questions / upgrading from atk 11.8 to atk 12.2

« on: June 7, 2012, 08:02 »

dear sir,
     we are currently running atk 11.8  with a license server..we wish to upgrade it to 12.2
     can you please suggest how to proceed..
                                      thanking you beforehand

6

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 24, 2012, 11:16 »

It is at least good if you can motivate the choice of the distance, if you don't optimize it.

Sir,
    I have the licence for EHT and I wish to optimize my Au-Cnt-Au structure as mentioned above.
    But the tutorial
    http://quantumwise.com/publications/tutorials/mini-tutorials/95-optimizing-the-geometry-of-a-two-probe-system
    suggests to use DFT,so will i have a correct optimized structure or not.....
                                                                              Thanking you in advance
   

7

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 11, 2012, 13:17 »

It is at least good if you can motivate the choice of the distance, if you don't optimize it.

Ok..
then i will first try the above geometry without optimization and then thereafter i will try to optimize the structure and compare both the results...(for optimization i will need your help again later)
i will inform you what result i get...
thanks a lot for everything.. 

8

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 11, 2012, 10:44 »

At least the distance between the tube and the surface should be carefully considered.

Thanks for the reply,..
I am keeping a distance of 2.2A between Au electrode and Carbon Nanotube according to the published paper
J. Palacios, P. Tarakeshwar, and D. M. Kim, Phys. Rev. B 77, 113403
2008
Will that be fine in carrying out the calculation without optimization..

9

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 11, 2012, 06:44 »

Click the + sign

Thanks a lot..
Sir,i now have the structure of cnt(5,0) in between Au(111) electrode..
Do I have to optimize the structure to obtain proper results or without optimization also,i will get fair results in calculating transmission spectrum,DOS,etc..

10

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 10, 2012, 15:30 »

In principle it shouldn't be a big problem if there is enough screening. 3-4 layers are perhaps on the bit on the low side to consider the screening complete, however. But, I doubt it will be critical. Still, if you are concerned, it would be easy enough to add a 4th layer on the right in the Builder, just add 33.3333% of the electrode to the right surface.

Thank you for your generous reply..
But when i open it in the builder it already shows 33.3333% of the electrode to the right surface. So,can u just suggest me how to insert the 4th layer..

11

General Questions and Answers / Re: How to get electrode coordinates for two probe system

« on: January 10, 2012, 10:32 »

This will be so much easier to do in ATK 12.2. We are currently make a completely new Builder, where this system is one of the test cases, which we are making sure is easy to build.

So, since that is coming out relatively soon, but not tomorrow, I decided to make the simplest solution possible (for me) which anyway works in 11.8.

The result is the quick-and-dirty Custom Builder attached to this post. How way to use it:

• First save this script on your computer.
• Then, drop it (the file) onto the "Custom" icon in VNL.
• You can drop any cubic metal like Cu or Au or Pd etc onto the "New electrode" dropzone (default is gold). It must be cubic because we need to cleave it. A simple extension would be to allow also ready electrodes; then one could also build pure nanotube or graphene junctions
• Now open another Custom Builder and select Nanotube from the menu. Choose the indices you want, and remember to repeat it so it's long enough.
• Then drag and drop the nanotube, using the script icon in the lower right-hand corner, onto the dropzone "Drop center bulk here".
• Now you can make some adjustments in terms of repetitions (in X/Y) distances etc so that you get something reasonable.
• Note that you can actually take any bulk system and put in the middle. So also some piece of graphene would work fine.

One thing you may want to "post-process" is to rotate the tube, or fine-tune it's position. This can be done in the Builder, by selecting all carbon atoms (right-click background, Select>Select by>Elements), and then use Transform>Rotate or Translate.

Let me know if you find any mistakes or problems with using it.

Dear Sir,
           I am trying to build a carbon nanotube transistor using the above script in which i have inserted a nanotube(5,0) in between Au(111) electrodes. As mentioned above,i followed the steps but at last it seems to have 4 layers of Au at the left surface and 3 layers at the right surface of the scattering region. Will this hamper my transport calculation..
                    thanking you in advance