Negative refractivity assisted optical power limiting

We propose an approach for achieving optical power limiting (OPL) using planar multilayered media. The approach involves the use of multiple bilayer structures that consist of a negative index (NIM) layer followed by a nonlinear two-photon absorbing (TPA) layer. The NIM layers refocus light in the TPA layers to increase intensity and nonlinear absorption. We perform parametric two-dimensional finite difference time domain simulations and compute the power transmittance of the media as a function of the incident light intensity, the number of layers, the layer thickness, and the material properties. Our analysis demonstrates proof-of-concept and indicates that the TPA-based OPL can be enhanced and optimized using NIM focusing.