Principles of Electromagnetic Waves and Materials, 2nd Edition

10Spatial Dispersion and Warm Plasma*

In Chapter 9, we discussed wave propagation in cold isotropic plasma. The effects of dispersion, to be more precise, temporal dispersion, are emphasized. In literature, cold plasma is sometimes referred to as “temperate plasma” [1,2]. The permittivity of warm plasma, in addition to being the function of the frequency ω, is also a function of the wave number k. For this reason, the warm plasma is said to be spatially as well as temporally dispersive [1,2,3]. Metal at optical frequencies can be modeled as warm plasma [4], the Fermi velocity playing the role of the thermal velocity of the warm plasma. While the model based on the cold plasma is said to represent local optics, the warm plasma model represents ...