QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Lim changmin on May 27, 2025, 08:32

Title: hartree difference potential problem
Post by: Lim changmin on May 27, 2025, 08:32

Hello,

I'm currently trying to calculate the Hartree difference potential (HDP) for a silicide/silicon contact and visualize it alongside the projected local density of states (PLDOS), as shown in the QuantumATK tutorial here:
https://docs.quantumatk.com/tutorials/ag_si_interface/ag_si_interface.html

However, the HDP results I obtained are not what I expected. I assumed that the HDP would show a peak near the interface and then gradually decrease, clearly indicating the Schottky barrier height. But the resulting graph looks quite different from this expectation.

For reference, I used silicon region lengths of 70 Å and 100 Å in separate calculations. I also attached the structure file that I used

Could anyone help me understand why the HDP results might appear unusual or inconsistent with expectations?

Thank you in advance for your help!

Title: Re: hartree difference potential problem
Post by: Anders Blom on June 6, 2025, 23:34

The second graph seems to be a non-converged calculation, maybe. The first one looks good though, although the contact appears Ohimic. Maybe the lack of a Schottky barrier is related to the dangling bonds in the Si/CoSi interface; the terminating Si atoms on both sides are undercoordinated?