:<math> \varepsilon(\omega) = \varepsilon_{\infty} - \sum_{p=1}^N \dfrac{{\omega_p}^2}{\omega^2 - j\omega \nu_p} </math>
where <math>\omega_p</math> and <math>\nu_p</math> are the angular plasma frequency and angular collision frequency corresponding to the p''th'' pole, respectively, and both are expressed in rad/s. For an unmagnetized plasma, <math>\varepsilon_{\infty} = 1</math>1. A Drude pole with ω<sub>p</sub> = 1.803×10<sup>11</sup> rad/s, and ν<sub>c</sub> = 2×10<sup>10</sup>rad/s is used as the dispersive model for this project.
Figure 3 shows the geometry setup for the periodic unit cell of the Drude plasma slab in [[EM.Tempo]]. A box of dimensions 10mm × 10mm × 15mm is considered, with lateral periods of 10mm along both X and Y directions. The top and bottom domain walls are assumed to be convolutional perfectly matched layers (CPML). The periodic structure is excited using a normally incident plane wave source.