Ultra-fast all-optical switching based on nanoantenna coupled to monolayer TMDs

• Main Author: Song, Qige
• Other Authors: Luo Yu
• Format: Thesis-Master by Coursework
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics; Engineering::Electrical and electronic engineering::Nanoelectronics
• Online Access: https://hdl.handle.net/10356/169844
• Institution: Nanyang Technological University

Transition Metal Dichalcogenides (TMDs) have shown great potential for applications in areas such as light capture, photodetection, phototransistors, light emitting diodes and nanolasers due to their excellent optoelectronic properties. They are currently one of the frontiers of research. The band gaps of few-layer TMDs are in the visible and near-infrared regions, and their excitons have considerable binding energies at room temperature, high resonant oscillator strengths, and valley-selective circular dichroism due to spatial inversion symmetry breaking, which make TMDs particularly attractive. These properties make the TMDs attractive. The surface plasmon polaritons of metal nanostructures have subwavelength properties, and their resonant wavelength, spectral width, near-field enhancement multiplier and far-field radiation properties can be flexibly controlled through rational structural design. The combination of the plasmon polaritons optical structure and TMDs can significantly broaden the fundamental research on the frontier of nanophotonics and the design and application of nanophotonic devices. In the dissertation, a spatial all-optical switch based on dimer and monolayer TMDs is designed. The feasibility of the Rabi splitting generated by the plasmon polaritons system under strong coupling is demonstrated through the analysis of the transmission and scattering spectrum of the designed all-optical switch for the design of an all-optical switch. In addition, some physical parameters of the structure, such as the type of precious metal, dimer width and dimer gap distance, were varied and simulated. The best choice of the set variable was found through the analysis of the results: a monolayer TMDs coupled to a gold dimer with a dimer width of 40 nm and a gap distance of 12 nm. The variability broad wide applicability of this structure is also demonstrated.