QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: chethankumar_m on March 12, 2017, 17:19

Title: electron density
Post by: chethankumar_m on March 12, 2017, 17:19

Hi,
how to calculate the electron density of any 2d material (example: MoS2) at the edge of conduction band?
Thanks in advance....

Title: Re: electron density
Post by: Petr Khomyakov on March 12, 2017, 18:20

Do you mean the density of electronic states at the edge of the conduction band? Otherwise, what is your definition of  "electron density" at the edge of the conduction band?

Title: Re: electron density
Post by: zh on March 13, 2017, 02:09

Quote from: chethankumar_m on March 12, 2017, 17:19

Hi,
how to calculate the electron density of any 2d material (example: MoS2) at the edge of conduction band?
Thanks in advance....

Please look at:
http://docs.quantumwise.com/manuals/Types/BlochState/BlochState.html#blochstate-c

The wavefunction at a given k-point and eigenvalue  can be accessed.

Title: Re: electron density
Post by: Anders Blom on March 13, 2017, 19:28

There is an old post on this topic, http://quantumwise.com/forum/index.php?topic=2203 (also see http://quantumwise.com/forum/index.php?topic=3771). These are more applicable to older versions of ATK, there are some prettier ways to collect and visualize the data today, but at least it gives an indication of the possibilities.

Title: Re: electron density
Post by: chethankumar_m on March 16, 2017, 11:26

Thank you for your replay. I am calculating the mobility. so, is it possible to extract carrier concentration out of this file? if it can be done please brief on it, if not please suggest the method for calculating the carrier concentration for MoS2.

Title: Re: electron density
Post by: Anders Blom on March 16, 2017, 17:08

No. The carrier concentration needed for mobility is related to the doping level, and this is an input to the calculation, not an output. I don't think your approach for the mobility via that particular tutorial is fruitful, rather you should look at http://docs.quantumwise.com/tutorials/mobility/mobility.html

Title: Re: electron density
Post by: lida_A on November 17, 2017, 20:34

I was wondering if the carrier concentration as a function of Fermi-level is calculated using integration of [DoS(E)f(E)dE]?

Thanks

Title: Re: electron density
Post by: Anders Blom on November 18, 2017, 20:39

Well, it's more the opposite - given a carrier concentration, you obtain the Fermi level from solving that equation. In a real-life situation, you don't know the Fermi level, but you (hopefully) know the doping concentration.

Title: Re: electron density
Post by: lida_A on November 20, 2017, 18:27

Thanks for the reply. Actually, I would like to compare the carrier concentration obtained from Hall measurements (real-life situation) with DFT-based calculations. So, I guess this is the way to do it. Thanks again.