Messages

1

General Questions and Answers / strain

« on: May 15, 2017, 15:20 »

Hello everyone,

1) Is there a way to apply strain in the entire Central Scattering region (including electrode extensions) keeping the electrodes unstrained?
2) And should force & stress optimization be done after applying strain? If so, then for stress optimization, which directions should be kept unconstrained for uniaxial and for biaxial strain? 

2

General Questions and Answers / Re: transmission spectrum

« on: May 8, 2017, 12:42 »

Here are the transmission spectra of bulk and the device from bulk.
The bulk one is clearly different from the latter. Also tr. spectrum of bulk shows integral values of transmission while the other one shows all real values. Why so?

3

General Questions and Answers / transmission spectrum

« on: May 8, 2017, 11:40 »

What difference does it make while calculating the bulk transmission spectrum and the device transmission spectrum with the electrodes made up of the same material as the scattering region?

4

General Questions and Answers / Re: missing bonds after optimization

« on: March 28, 2017, 02:22 »

Thanks a lot.

5

General Questions and Answers / missing bonds after optimization

« on: March 27, 2017, 19:31 »

After optimizing a Phosphorene sheet doped with a Sulphur atom, the bond between the S atom and adjacent P atom vanished, although the bond length between them is in accordance with previous reported results. Keeping the bond length same, can the bond be made to reappear? What is the criterion which ATK applies to show a bond between 2 atoms? 

6

General Questions and Answers / Re: Why do we modify values of primitive vectors when study a monolayer nanoribbon

« on: March 27, 2017, 11:18 »

Suppose
1) a nanoribbon (3 unit cells along B and 4 unit cells along C) is in BC place with C being the transport direction and vacuum space being added along A and B  direction; and
2) same 3x4 structure but vacuum padding only along the A direction such that it is a nanosheet.

Now, what do the 2 structures, in real, represent? In other words, if we take a  real graphene sheet which has 3 units along zigzag and 4 units along armchair, will it be called a nanosheet or nanoribbon; and to which case (1 or 2) will  it correspond to? I hope I am clear. Thanks.

7

General Questions and Answers / Re: biomolecule attached to graphene

« on: February 2, 2017, 13:11 »

Thanks.

8

General Questions and Answers / biomolecule attached to graphene

« on: February 1, 2017, 15:22 »

Hello,
 in the paper -
R. Chowdhury, S. Adhikari, P. Rees, S.P. Wilks, F. Scarpa
Graphene-based biosensor using transport properties
Phys. Rev. B, 83 (2011), pp. 045401-1–045401-8

the H-atoms of an anthracene molecule are shown to be attached to those of the graphene . Please can anyone clarify what is the type of bonding and how it can be constructed in ATK. Thanks.