QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: ph on July 11, 2013, 14:52

Title: Is it transvers average transmission or total transmission ?
Post by: ph on July 11, 2013, 14:52

Dear Sir,

I performed transport calculation and obtained transmission spectrum for my 2D sheet(x-z plane) and . The relevant script is as follows.

transmission_spectrum = TransmissionSpectrum(
    configuration=device_configuration,
    energies=numpy.linspace(-2.0, 2.0,401)*eV,
   kpoints=MonkhorstPackGrid(23,1),

energy_zero_parameter=AverageFermiLevel,
    infinitesimal=1e-06*Units.eV
    )
 
What kind of transmission is it giving? Is it only Longitudinal  transport along Z-direction? or  Average transverse transport along X-direction? or  Sum of both longitudinal and transverse transport?

2) What modification do I need, If I want to have transmission spectrum or current only in transverse direction?

3) How to get(or combined) total current(sum of longitudinal and transverse)?    or total transmission spectrum?

Kind regards
 

Title: Re: Is it transvers average transmission or total transmission ?
Post by: Anders Blom on July 21, 2013, 23:27

Only transport/current along Z is considered in ATK, however the incident wave vectors may have finite kx and kz components, which are assumed to be conserved across the tunneling barrier. When you include k-point sampling in the transverse directions (kx and ky), the resulting transmission spectrum is the average over these modes.

Title: Re: Is it transvers average transmission or total transmission ?
Post by: ph on July 27, 2013, 11:47

Thanks a lot for your kind reply.