The bulk plasmon energy of ZnO is 18.8eV so ofr a thin foil I expect a surface plasmon at around 10eV. Does anybody know a reference where this was actually measured to within eV accuracy or better?
The plasmon energy of Zinc Oxide is strongly dependant on the carrier concentration, which varied quite dramatically depending on growth conditions
See for example;
Article Mid-infrared surface plasmon resonance in zinc oxide semicon...
Hello Miftahussurur,
I used the approximation E_sp≈E_p /sqrt(1+epsilon). This would suggest ~6eV for epsilon=8.5 and E_p=18.8eV, but I think this may be too low.
Hello Thomas,
I think that all the values in the IR published (
For the surface/bulk plasmon polariton the plasma frequency for free carriers is directly related to concentration - aka the doping (see Maiers Plasmonics, for example).
However, the fact you have such a high plasma energy implies that you are looking at very different physics (The plasma frequency for gold is only 9.6eV) - What are you using to define the plasma energy?
yes, but I was not talking of polaritons anywhere: as far as I understand surface plasmon polaritons assume a free electron on the surface and so can only occur on metals. I am considering plasmons excited by fast (>keV) electrons polarising many atoms in (bulk) and on (surface) of any material simultaneously.
So the number density of electrons contributing can be much higher and the effectice mass lower, so the plasmon frequency and hence plasmon energy are much bigger (several eV) than in the polariton (several ten meV) case.
Dear Thomas Walther
the pic which is attached, compares the plasmon frequency for some materials
i hope this be helpful