Efficient Computational Model for Light Propagation in High Scattering NP-doped Optical Fiber

Faculty Development Competitive Research Grant Program (General) 2024-2026

Based on the accumulated experience in the field of high scattering optical fiber and based to the preferential collaboration with material scientist that fabricate NP-doped fiber, we aim at designing and developing an innovative numerical model for describing and simulating the backscattering behavior of NP-doped fibers. The simulation system proposed in this project will present the following peculiarity:
• Since the problem accounts for the 3D propagation of light in high scattering disordered material, namely a long and thin optical fiber, we decided to decompose the structure to analyze in several building blocks, i.e., sections of fiber of maximum 0,5 mm long. Each building block will present a different random distribution of nanoparticles according to the fabrication specs. We intend to characterize the building blocks by using a modified FDTD method and obtaining the Absorption, Reflection and Transmission characteristics over the spectrum of interest.
• Alternatively, we can evaluate the short modal propagation inside the building block by implementing a custom BPM.
• We are interested of creating a database of building blocks which will be mounted together by using a linear method like an intensity based TMM.
• Since a complete 3D FDTD simulation of a NP-doped fiber, which can be meters long, cannot be achieved by the calculation power of any current available HPC, we aim to create a database of 3D building blocks large enough to achieve a sufficient description of the disordered behavior of the fiber. It will be the random combination of the building block through the linear TMM that will finish the characterization of the fiber. So, the method can be described as a Hybrid 3D + 1D Propagation Method.
• The proposed hybrid method is intended to be fast and computationally efficient.
• Careful testing and validation: the numerical method will be carefully tested, calibrated and validated by comparing the numerically obtained result with the experimental results that we have accumulated during the past years of study of High Scattering NP-doped fibers. Moreover, the established collaboration with Nice laboratory, in France, will be a relevant platform for validating the numerical results by directly interact in the process of fiber design.