Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in sl...Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in slow acquisition.In this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive imaging.The cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral response.We demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.展开更多
基金H2020 Future and Emerging Technologies(MIRBOSE 737017)French RENATECH network.
文摘Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging systems.However,owing to their low average powers,only raster-based images can be taken,resulting in slow acquisition.In this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive imaging.The cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral response.We demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.