Messages

1

General Questions and Answers / How are the positive and negative gate voltages defined in QuantumATK

« on: August 7, 2021, 09:26 »

Dear QuantumATK users,
     I want to ask you how to apply gate voltage to the devices in QuantumATK. For example, for a double gate device, is the applied gate voltage equal to the difference between the applied gate voltage to the upper gate minus the gate voltage to the lower gate？
    Thank you！

2

General Questions and Answers / How to calculate ProjectedLocalDensityofStates by IV charateristics?

« on: September 18, 2020, 10:24 »

Dear ATK users:
          When i calculate the ProjectedLocalDensityofStates (PLDOS) by adding analysis after IV charateristics, there is no end of calculation of  PLDOS. However, there is no error in the file  ".o".   In the file of ".out",  the results are unfinishied.  I do not know what is the wrong  and how to solve this problem? Look forward to your reply, thank you !

3

General Questions and Answers / Re: the relationship between the dielectric constant and the transport properties

« on: October 22, 2019, 03:45 »

Thanks for your reply. I'm sorry for not being able to clearly explain my problem. Here's my question that  the calculation of the transmission spectrum are different between when I do not add dielelctric and the gate voltage, and  when I add dielectric layer and the gate voltage, but set the gate voltage is 0.  I don't know why and  I am not very clear that how to influence the transport properties of dielectric layers. Is there a formula to describe it?  Looking forward to your reply.

4

General Questions and Answers / the relationship between the dielectric constant and the transport properties

« on: October 15, 2019, 16:05 »

Hello everyone，
        I had a problem when I calculated the transport properties. The transmission spectrum of the field effect transistor with or without a dielectric layer is different, but the parameters are the same. I want to know how does the dielectric layer affect the transport properties and is there a formula describing the relationship between the dielectric constant and the transport properties?
       Looking forward to your reply. Thank you.

5

General Questions and Answers / Re: work function and Fermi level

« on: April 27, 2019, 04:26 »

           Thank you for your reply. I have other questions. First, i want to know that if i  use th same parameter setting, what is the relationship between the work function and the Fermi level. Second, i want to know that  the the work function is the bulk of metal or metal surface.
           Look forward to your reply. Thanks.

6

General Questions and Answers / work function and Fermi level

« on: April 26, 2019, 09:04 »

Dear ATK staff and users:
      I have a question about work function,Fermi level and vacuum level. I have calculated the Fermi level and  work function of metel. However, i found that the  value of Fermi level  was different from work function, so i want to know that how are vacuum levels defined. Are the vacuum levels different in different systems?
     Looking forward to your reply. Thanks.

7

General Questions and Answers / How to solve this question?

« on: March 21, 2019, 10:22 »

Dear all:
       When i calculated the transmission uhder the bias of zero,the erro occured. But i don't know the reason. I hope to get your reply. Thanks all.

8

General Questions and Answers / Spin-orbit coupling

« on: January 17, 2019, 15:22 »

Dear all
           I have a question about Spin-orbit coupling. When i calculate the SOC, i am not sure how to set the initial state? Whether the initial spin state is necessarily related to SOC? 
          Thanks all.

9

General Questions and Answers / Re: Fat Bandstructure

« on: January 11, 2019, 04:12 »

Thanks for your reply. I will try it again.

10

General Questions and Answers / Fat Bandstructure

« on: January 10, 2019, 09:31 »

Hi all:
      I have a question about how to draw Fat Bandstructure  in origin , and the data is derived from ATK.  Hope to get your reply, thank you!

11

General Questions and Answers / Re: Why can't device from bulk be implemented along the c direction?

« on: January 3, 2019, 03:15 »

Thanks for your reply. I will try again.

12

General Questions and Answers / Why can't device from bulk be implemented along the c direction?

« on: January 2, 2019, 14:39 »

When building devices，device from bulk can be realized before optimization(graphdiyne-V2C.py). Why can't device from bulk be realized along the transportation direction after optimization(graphdiyne-V2C-opt.py)? I hope to get your reply. Thanks.

13

General Questions and Answers / Re: OverflowError: (34, 'Numerical result out of range')

« on: November 19, 2018, 09:31 »

Thank you very much for your reply. The weak intermolecular interactions refers to weak interaction between aromatic rings.Thanks .

14

General Questions and Answers / Re: OverflowError: (34, 'Numerical result out of range')

« on: November 15, 2018, 08:52 »

Thanks for your reply. I will try the method you provide. Since the system needs to take into account weak intermolecular interactions and needs to use semiempirical functional, I used DFT-1/2.

15

General Questions and Answers / Re: OverflowError: (34, 'Numerical result out of range')

« on: November 14, 2018, 13:21 »

Thanks for your reply.  These are my files.