Electrode and electrode extension size

[gozde]

Hi all,

My results obtained from transport calculations vary with electrode size. The results I obtained when the minimum electrode size is one unit cell i.e. 3.7 ang and the electron extension is two unit cells i.e. 7.4 ang (QATK default) are quite different from when the minimum electrode size is two unit cells i.e. 7.4 ang and the electrode extension size is two units cells, i.e. 7.4 ang. I wonder, which parameter do we need to change in order to obtain accurate results? Is it the electrode size or the electrode extension size?

[Anders Blom]

The results do not depend on the electrode size, but they do depend on the extension size.

[gozde]

Thank you Dr. Blom, I got it.

[gozde]

Hello again Dr.Blom,

I try to understand how length of the electrodes affects the IV curve of the our device model. Therefore I have made some tests.

I have noticed that, when I increase the electrode extension length, minimal electrode length is also increased to be the same as the electrode extension length. However if I have first increased the size of the central region at the interface of the respective electrode, and secondly I have increased the electrode extension length, minimal electrode length remains same. What is the origin of this difference and which geometry makes sense?

I look forward to hearing from you.

[AsifShah]

Hi,
Can you check the case where you observe an increase in electrode length when increasing electrode extension length. In that case, is there a distortion/grain boundary kind of thing at the interface between electrode extension and electrode?