Messages

1

General Questions and Answers / HSE or any hybrid functional available in the ATK?

« on: March 26, 2018, 04:01 »

Hi,

Is HSE functional available in the ATK?

Or any hybrid functional available?

If yes, any separate license needed to use it?

Thanks in advance,

2

General Questions and Answers / Re: Access to the past webinars?

« on: December 19, 2017, 12:45 »

OK, Thank you

3

General Questions and Answers / Access to the past webinars?

« on: December 18, 2017, 19:25 »

Hi, is there any offline version of the past webinars ? eg. I am interested in the webinar on how to include electron-phonon scattering effects in large scale atomistic electronic device simulations.

Best regards,

4

General Questions and Answers / Re: Copy data from one .nc file to another?

« on: February 14, 2017, 18:08 »

Found a way to do that.

Thanks.

5

General Questions and Answers / Re: Copy data from one .nc file to another?

« on: February 14, 2017, 15:18 »

I did that but it does not calculate the effective mass it just stays there forever showing calculating effective mass and do nothing. I use version 2016.3 .

I do not have this problem when the .nc file contains the bulk configuration. For those, I can use the effective mass analyser button at the bottom of the bandstructure and I get the effective mass calculated. But it does not work

Can you suggest how to fix this?

However, is there any way to copy data from one .nc to another one?

Thanks in advance,

6

General Questions and Answers / Copy data from one .nc file to another?

« on: February 14, 2017, 14:06 »

Hi,

I have calculated bandstructure from a configuration but have saved that into a seperate .nc file, so now I have one .nc file which contains start configuration and optmized configuration and another .nc file which contains only bandstructure.

I want to calculate effective mass now but when I only read the .nc file which contains bandstructure it does not work and I get error.

How can I copy the bandstructure form the seonc .nc file to the first .nc file which contains bulk_configuration?

I appreciate if you can help me regarding this.

Thanks in advance,

7

General Questions and Answers / Re: can ATK find semiconductor contribution to the bandstructure in the interface

« on: November 11, 2016, 18:54 »

Hi,

Any updates on this "contribution-resolved band structure" feature as the 2016.3 version is already out?

Thanks,

8

General Questions and Answers / Boundary conditions for transport simulation

« on: September 27, 2016, 22:16 »

Why in Quantumwise  Dirichlet boundary conditions is used for the potential at the source/
drain contacts when solving the Poisson equation for a nanowire?

Does not Diriclet boundry condition limit the potential in the source/drain from following the distribution imposed by quantum mechanics^[1]?

Should not one use Neumann boundary conditions for the potential at the source/drain contacts  to maintain charge neutrality?


[1] A. R. Brown, A. Martinez, M. Bescond and A. Asenov, "Nanowire MOSFET variability: a 3D density gradient versus NEGF approach", Silicon Nanoelectronics Workshop, 10–11 June, Kyoto, Japan, pp. 127–128 (2007)

9

General Questions and Answers / Re: Pseudopotentials with fractional charge

« on: September 6, 2016, 08:09 »

So is it OK if I use HGH or other pseudopotentials for any atoms in my system while using  FHI pps for the passivating hydrogens of the the same system?

10

General Questions and Answers / Pseudopotentials with fractional charge

« on: September 5, 2016, 12:15 »

Hi,
What  pseudopotential with fractional charge for hydrogen atom are available in quantumwise? the only one I can find is FHI LDA .pz but I need to use more accurate pseudopotentials like HGH or sg15,

are there any other pseudopotential with fractional charge available in quantumwise?

Regards,

11

General Questions and Answers / Re: MGGA does not seem to produce the correct bandstructure

« on: September 5, 2016, 12:05 »

Thanks a million Daniele,

I will try what you have suggested.

Regards,

12

General Questions and Answers / Re: MGGA does not seem to produce the correct bandstructure

« on: September 1, 2016, 22:28 »

Thanks a million, looking forward to their reply.

13

General Questions and Answers / Re: MGGA does not seem to produce the correct bandstructure

« on: September 1, 2016, 15:31 »

Dear Daniele,

While I was looking around I found the following paper which Quantumwise is a co-author:

http://www.sciencedirect.com/science/article/pii/S0038110115002580

Would you please let me know what was the approach to get the c-parameter value?

Thanks a million for your help,

Regards,

14

General Questions and Answers / MGGA does not seem to produce the correct bandstructure

« on: September 1, 2016, 02:08 »

Dear Support,

I have struggled to get the bandstructure for a using MGGA for quite a while now,

The band structure of a relaxed nanowire without using MGGA seems alright but underestimated, when I use the MGGA the band gap seems to be not correct. Moreover the fermi-level is not in the middle of bandgap when using MGGA as oppose to bandstructure calculated without MGGA.

I have attached the band structure with and without MGGA as well as only coduction bands for more clarity.

Regards,

15

General Questions and Answers / MGGA basis set/exchange correlation

« on: August 25, 2016, 15:44 »

Hi,

Woulld you please explain why no matter what we choose  in predefined functional,  exchange and correlation in vnl for MGGA the pseudopotential stays the same (LDA.PZ)?

Another question is that If I want to relax the structure before using the MGGA to get the bandstructure what type of pseudopotential you suggest to use? LDA.PZ or GGA PBE?

I was going to use GGA.PBE but I cannoft figure out how to change the MGGA pseudopotential to GGA.PBE

Thanks in advance,

Regards,