Defect mode in the bulk plasmon-polariton gap for giant enhancement of second harmonic generation

Giant Second-Harmonic Generation in Cantor-like Metamaterial Photonic Superlattices

“…The use of strong light–matter interaction in the bulk PP gap combined with nonlinear properties of photonic superlattices to produce giant enhancements of SHG efficiency has been already demonstrated. 35 Here, we are interested in the analysis of two competing effects: first, increasing N diminishes the amount of LiNbO 3 material in the unit cell as , which we may expect to be reflected in a reduction of the nonlinear effects. Second, localized modes with enhanced amplitudes are excited by increasing the self-similarity properties of the unit cell, because of the amount of disorder introduced by the fractal aspects, which must improve the second-order nonlinear interaction in the right-hand side of eq 4.…”

“…FF (SH) frequencies were selected as ν FF = 5.8986 GHz (ν SH = 11.7972 GHz), ν FF = 5.9205 GHz (ν SH = 11.841 GHz), and ν FF = 6.0258 GHz (ν SH = 12.0516 GHz), for N = 1, 2, and 3, respectively. The use of strong light–matter interaction in the bulk PP gap combined with nonlinear properties of photonic superlattices to produce giant enhancements of SHG efficiency has been already demonstrated . Here, we are interested in the analysis of two competing effects: first, increasing N diminishes the amount of LiNbO 3 material in the unit cell as , which we may expect to be reflected in a reduction of the nonlinear effects.…”

“…The latter originates from the resonant coupling of the magnetic/electric field component of light with the corresponding plasmonlike μ B (ω)/ε B (ω) effective response under transversal electric/magnetic (TE/TM) polarized light, which cannot be observed in all-dielectric superlattices. The bulklike PP gap edges and the PP defective mode were used for the giant enhancement of SHG in the microwave and terahertz regimes, 35 where the intrinsic losses of metallic building blocks were shown to have a detrimental effect on the SHG in the high-frequency regime.…”

“…36 Self-similarity properties of these nonlinear structures can also be used to extend the results to be presented for broad-band SHG applications, 36−38 which cannot be reached, for example, using defect modes. 35…”

“…This is in contrast with Thue–Morse- and Fibonacci-like superlattices, where the unit cell thickness increases with the sequence step . Self-similarity properties of these nonlinear structures can also be used to extend the results to be presented for broad-band SHG applications, − which cannot be reached, for example, using defect modes …”