Figure 9

(a) The frequency variation of real and imaginary parts of the relative permittivities \((\varepsilon _t,\varepsilon _g)\) and \((\varepsilon _t'=\varepsilon _p,\varepsilon _g')\) characterizing the two InAs-based media (one of which plays the plasmonic role) incorporated at each unit cell, across the mid-infrared band. (b) The quantities \(|\varepsilon _t+\varepsilon '_t|=|\varepsilon _t+\varepsilon _p|\) and \(\text{Re}(\varepsilon _t)+\text{Re}(\varepsilon '_t)=\text{Re}(\varepsilon _t+\varepsilon _p)\) indicating what is the frequency around which the proposed concept can be best applied. Plot parameters: \(\varepsilon _{\infty }=12.3\), \(\omega _{p}/(2\pi ) \cong 124.2~\text{THz}\), \(\omega _{c}/(2\pi ) \cong 1.4~\text{THz}\), \(\omega '_{p}/(2\pi ) \cong 105.9~\text{THz}\), \(\Gamma /(2\pi )= 0.3~\text{THz}\).