[Archive] surface potential dependence on material

Message by Sanat Tiwari:
Dear users and developers,
I am getting a sharp difference in surface potential when trying a metal (like gold, Alox etc) and a dielectric (like Kepton etc…). Even when I am keeping both species Bolzmann type to reproduce OML, for Kepton or other dielectrics, it is matching nicely while for metals it is quite different.
Can someone help in understanding the differences !!

Message by Jean-Charles Mateo-Velez:
Did you use secondary electron emission ? To fit OML, the best is to perform run without secondary electron emission processes of course.
Also what is the size of your spacecraft/probe with respect to Debye length (OML is valid for large Debye length) ?
Another possibility concern the electrical circuit. Did you put all super electrical node to the same voltage using circuit.txt ?

Message by Sanat Tiwari:
Dear Dr. Jean-Charles Mateo-Velez,
I took care of switching off secondary electron emission and photo emission. GEO simulation parameters taken. Just taking a sheet with two different materials (like Kapton and Alox). No circuits given. Size of object is 0.1 cm to 1 cm which is far less than Debye length. Plasma environment size is 4-5 times larger.
The problem is persisting for all problems where metal/conducting materials being taken. For dielectrics, the potential is coming of order KV and for metals, it is few V.
All the issues are coming only when switching off photo electron emission.
Electrons are Boltzmann and ions are BacktrackingPICVoldistrib.
I would really be thankful for your kind help.