For typical metals such as copper or silver, " n _ \ mathrm { e } " is approximately 10 23 cm " 3, which brings the plasma frequency into the ultraviolet region.
32.
Where f _ p is the plasma frequency as above, f is the frequency of the radio signal, and f _ c is the " collisional frequency " of the atoms in the air.
33.
Because its plasmon frequency is in the IR-range { { cite journal | doi = 10.1021 / jp026600x | title = Indium Tin Oxide Plasma Frequency Dependence on Sheet Resistance and Surface Adlayers Determined by Reflectance FTIR Spectroscopy
34.
At low " k ", the SPP behaves like a photon, but as " k " increases, the dispersion relation bends over and reaches an asymptotic limit called the " surface plasma frequency ".
35.
This sensitivity as compared to the cathode voltage sensitivity, is reduced by the ratio ? q / ?, where ? q is the angular plasma frequency; this ratio is of the order of a few times 10 " 2.
36.
It exists under the condition that the permittivity of one of the materials forming the interface is negative, while the other one is positive, as is the case for the interface between air and a lossy conducting medium below the plasma frequency.
37.
When the negative voltage ( few KV's ), the resultant electric field drives electrons away from the substrate in the time scale of the inverse electron plasma frequency ? e " 1 ( ~ l0 " 9 sec ).
38.
However, in a sufficiently dense plasma ( " n " e > 2.5?0 30 m " 3, a density greater than that of a solid ), the cyclotron frequency is less than twice the plasma frequency.
39.
Basically, if the EM wave is " slow " enough ( has a frequency below the plasma frequency of the metal ), the electrons in the metal ( which are delocalized, as you said, and mostly unbound ) can match its pace perfectly.
40.
It exists under the condition that the permittivity of one of the materials forming the interface is negative, while the other one is positive, as for example the interface between air and a lossy conducting medium such as the terrestrial transmission line, below the plasma frequency.