QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Dipankar Saha on September 8, 2015, 19:23

Title: e-ph coupling / IETS spectra...
Post by: Dipankar Saha on September 8, 2015, 19:23

Hi,
I wanted to know that_
1) Do you only consider the channel region.....while calculating e-ph coupling.....?!!
If so.....then I have a very odd question.../ Can I change the direction of transport...say top to bottom....? More precisely.....even if I swap the axes...to make things  such that the transport direction is always "Z"...but, can there be any discontinuity inside (just as much as the inter layer distance) the channel region??
2) Besides, is there any plugin or, script for finding the plot of ...."[ (d²I/dV² ) /(dI/dV)]   v/s.  bias voltage", considering the diff. kinds of vibrations..... ??

Best_
Dipankar

Title: Re: e-ph coupling / IETS spectra...
Post by: kstokbro on September 17, 2015, 13:45

please detail question 1, I do not understand it.

Regarding 2, there is a plugin to plot dI/dV vs V and d2I/d2V vs V. You can download the data and combine them to plot what you suggest.

Title: Re: e-ph coupling / IETS spectra...
Post by: Dipankar Saha on September 17, 2015, 14:13

Regarding question (1) _
What I was actually looking for....can somewhat be described by the cartoon drawn in the attached file....
Will there be any transport in z-direction...?

Thanks & Regards_
Dipankar

Title: Re: e-ph coupling / IETS spectra...
Post by: Anders Blom on September 17, 2015, 15:11

Of course - in any device in ATK, the central region can be anything - incl. defects, extra layers, and so on. But I'm also not sure I understand the exact question, because this cartoon is exactly a "normal" device for me, so why wouldn't there be transport? That is, I don't understand why it's not a normal device. Of course if the vacuum gap (?) is very wide, transport is suppressed but as long as there is a basis set overlap between atoms in materials A and B, the electrons can tunnel across the gap.

Title: Re: e-ph coupling / IETS spectra...
Post by: Dipankar Saha on September 17, 2015, 15:18

Actually I was thinking of a top contact and the bulk material beneath that.... /So, out-of-the plane transport can be found..as you mentioned (of course, I have to change the axes to make the "z"  as the transport direction... ) ....right??

Title: Re: e-ph coupling / IETS spectra...
Post by: Anders Blom on September 17, 2015, 15:34

There is no way to deal with "bending currents", the current must always propagate in one, independent direction.

Title: Re: e-ph coupling / IETS spectra...
Post by: Dipankar Saha on September 17, 2015, 15:48

Dr. Anders Blom,

Okay... I  see .... / Thank you very much for the reply... :)

Regards_
Dipankar