QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Dipankar Saha on February 8, 2019, 16:00

Title: Initial Density
Post by: Dipankar Saha on February 8, 2019, 16:00

Hi,
@ Device Algo. _ Initial Density:
What's the difference between  the types 'Neutral Atom' and 'Equivalent Bulk'?

Best_
Dipankar

Title: Re: Initial Density
Post by: Dipankar Saha on February 8, 2019, 16:02

What is the role of 'Electrode Constraint' ?? 

Title: Re: Initial Density
Post by: Petr Khomyakov on February 8, 2019, 21:40

Quote from: Dipankar Saha on February  8, 2019, 16:00

What's the difference between  the types 'Neutral Atom' and 'Equivalent Bulk'?

You may take a look at the two definitions of the initial density matrix for device calculations, https://docs.quantumwise.com/manual/Types/NeutralAtom/NeutralAtom.html and https://docs.quantumwise.com/manual/Types/EquivalentBulk/EquivalentBulk.html. One is constructed from individual atom densities, whereas the other one from the actual calculation of the central device region using periodic boundary conditions (i.e., bulk configuration).

Title: Re: Initial Density
Post by: Petr Khomyakov on February 8, 2019, 21:44

Quote from: Dipankar Saha on February  8, 2019, 16:02

What is the role of 'Electrode Constraint' ??

See the definition in the links in my previous reply. The self-consistent solution for device configuration does not depend on this parameter, just the convergence speed might change.

Title: Re: Initial Density
Post by: Dipankar Saha on February 9, 2019, 07:40

Okay.... Thank you  Petr!  :)