研究目的
Investigating the nonlinear effects and mechanisms of delayed THz response in metallic structures irradiated by femtosecond laser pulses, with a focus on the role of plasmonic resonances.
研究成果
The study concludes that laser-induced thermal effects in metallic structures can induce a delayed electromagnetic response in the THz range. The resonance character of THz response and its dependence on grating depth can be explained by considering the excitation, absorption, and diffraction of surface plasmons at optical frequencies. Non-quadratic conversion regimes may arise from temperature-dependent collision frequency of electrons.
研究不足
The model does not fully explain the THz response decrease when the grating depth is too large or when the foil thickness is reduced, due to unaccounted factors like anomalous heat diffusion and loss of continuity in experimental samples.
