Nonlinear LiNbO₃ topological Tamm interface state photonic crystal with static visible and intelligent laser protection

The rapid advancement of high-energy laser and LiDAR technologies imposes heightened demands on intelligent laser protection windows. Traditional laser protection devices often face difficulty in simultaneously achieving high absorption of low-energy laser and high reflection of high-energy laser. Herein, we investigate the efficacy of one-dimensional nonlinear LiNbO₃ topological Tamm interface state photonic crystal for static visible and intelligent laser protection applications. The photonic crystal's intelligent laser protection property arises from the amplification of nonlinear effects facilitated by the intense electric field localization surrounding the LiNbO₃ interface. At 1064 nm laser energy levels below 18.29 mJ/cm², the protection window exhibits up to 87.03 % absorption. When the laser energy increased to 83.84 mJ/cm², the reflectance reaches 88.07 % attributed to the unsatisfied amplitude matching condition caused by the LiNbO₃ nonlinear effect, thereby achieving successful intelligent laser protection. Furthermore, the fabricated sample demonstrates a maximum transmittance of 47.51 % in the visible wavelength range. This research provides novel insights into the development of multifunctional advanced optical elements.