Topics

1

General Questions and Answers / potential averaged over the B direction for a fixed A coordinate

« on: September 8, 2013, 17:38 »

Dear ATK developers and all,

May I know how to extract potential averaged over the B direction for a fixed A coordinate (A = 18 Angstrom) as you ploted in FIG. 1. and FIG. 5. (and also the Mulliken charge) in PHYSICAL REVIEW B 85, 165442 (2012). I would appreciate your help.

Best,
leslie

2

General Questions and Answers / charged electrode

« on: January 17, 2013, 09:35 »

Dear ATK developers and all,

I have noticed in the release letter of ATK ver. 12.2.2 that it is possible to use charged electrode. Is there any more detailed instruction demonstrating how to use such a function?  I would appreciate your help.


Best,
leslie

3

General Questions and Answers / k-resolved transmission dos

« on: September 1, 2011, 01:59 »

Dear Colleagues,

Anybody knows whether ATK can calculate the k-resolved transmission DOS? and how? I know that the software can map transmission coefficient at wave-vector space at Fermi level, but can we do the similar mapping for device transmission dos?

Thanks,
leslie

4

General Questions and Answers / MTJ with ferrimagnets as electrodes

« on: June 18, 2011, 14:35 »

Dear Colleagues,

Is it possible to carry on transport calculation with ATK 2011.2 for the stacking trilayer device like Fe-MgO-Fe, but using compensated ferrimagnets as electrodes instead of ferromagnets? Will this induce any unexpected mistake?

Thanks,

leslie

5

General Questions and Answers / how to define confinement orbital as hard_well in ATK basis set ?

« on: June 7, 2011, 08:50 »

Hi friends,

In Siesta, the basis set (atomic orbitals) is generated using a confinement potential. The default for this confiment potential is Sankey Hard Well (V=0 for r<a and V=infinity for r>a) in Siesta. An alternative (and better) confinement potential is soft-confinement potential V(r)=Voexp[-(rc-ri)/(r-ri)]/(rc-r).

In ATK, however, the only choice is soft-confinement potential, which is defined in the class ConfinedOrbital
 ConfinedOrbital(
principal_quantum_number,
angular_momentum,
radial_cutoff_radius,
confinement_start_radius,
additional_charge,
confinement_strength,
radial_step_size
)

Anyone knows what to do if I want to use the Sankey Hard Well potential instead of soft-confinement potential with ATK?

6

General Questions and Answers / how to set the initial spin for Fe/MgO/Fe MTJ

« on: June 1, 2011, 08:50 »

Dear all,

Recently I am trying to follow the tutorial Fe/MgO/Fe MTJ to learn how to calculate transport properties for such structures while encontering one question:

Why the initial spin of Fe atoms at the same electrode is set to the same direction? Shouldn't there exist both spin-up and spin-down ions within iron electrode?

leslie

7

General Questions and Answers / Restore scf result

« on: May 23, 2011, 18:21 »

Dear all,

I would like to know, in ATK11.2,  how to restore a self-consistent calculation result for further two-probe transport properties calculation given that I already have an  .nc file after scf run for the device system?
 
I have just switch to version 11.2 and find it is quite different from 08.10. In 08.10, we have a function named restoreSelfConsistentCalculation(). What is its equivalence in 11.2?

I would appreciate it if one example is provided together...

Many thanks.
leslie