Chirped grating for TE-five/TM-three reflective distribution feature

Abstract This research expounds on a novel reflective chirped grating, characterized by its differentiated functionality under various polarization modes. Under perpendicular incidence, this intricately grating produces a quintuple-channel diffraction output of the 0th, ±1st, and ±2nd orders in transverse electric (TE) polarization and a triple-channel diffraction output of the 0th and ±1st orders in transverse magnetic (TM) polarization. Both polarization modes exhibit excellent overall diffraction efficiency and uniformity. At an incident wavelength of 1550 nm, the diffraction efficiencies for the 0th, ±1st, and ±2nd orders under TE polarization are 20.16%, 19.27%, and 20.25%, respectively. Simultaneously, under TM polarization, the efficiencies for the 0th and ±1st orders are 31.79% and 31.57%, respectively. Grating parameters were meticulously derived using the finite element method (FEM) and subsequently corroborated through rigorous coupled-wave analysis (RCWA) to ensure superior grating accuracy. The study also exhaustively analyzes the manufacturing tolerances and robustness of the grating, affirming its practical applicability and effectiveness in practical applications. The dual-function grating splitter proposed in this paper enables the implementation of multiple functionalities within simple setups, suitable for applications requiring varied beam splitting. As photonic systems and fiber technology evolve, the potential applications of dual-function reflective splitters in these fields are increasingly highlighted.