Numerical investigation of photovoltaic and photodetector performances of Ag2BaTiSe4-based photonic devices

Abstract The investigation of eco-friendly and readily available materials for multifunctional optoelectronic applications is crucial to satisfy the increasing need for green energy and sophisticated photonic systems. In this work, a comprehensive numerical investigation of Ag 2 BaTiSe 4 -based photonic devices is carried out using the Solar Cell Capacitance Simulator in One Dimension to evaluate their potential for both photovoltaic and photodetector applications. A ZnSe/Ag 2 BaTiSe 4 heterojunction and a ZnSe/Ag 2 BaTiSe 4 /WSe 2 architecture incorporating a back-surface-field layer are systematically analyzed. Under optimized conditions, the ZnSe/Ag 2 BaTiSe 4 and ZnSe/Ag 2 BaTiSe 4 /WSe 2 structures achieve power-conversion efficiencies of 23.16% and 31.17%, respectively. Besides, essential photodetector parameters such as responsivity and detectivity are enumerated to evaluate the sensitivity and spectral response of the device. The results demonstrate the detectivity of 44.5 × 10 15 Jones at a wavelength of 980 nm and the responsivity of 0.69 A/W at a wavelength of 956 nm for ZnSe/Ag 2 BaTiSe 4 /WSe 2 device. The incorporation of the WSe 2 layer enhances the built-in potential, improves carrier selectivity, and suppresses rear-interface recombination, leading to significant improvements in both photovoltaic and photodetector performance. These findings highlight the strong potential of Ag 2 BaTiSe 4 for solar-energy harvesting and self-powered photodetection applications, while providing a theoretical foundation for future experimental development of Ag 2 BaTiSe 4 -based photonic devices.