Recently,computational sampling methods have been implemented to spatially characterize terahertz(THz)fields.Previous methods usually rely on either specialized THz devices such as THz spatial light modulators or comp...Recently,computational sampling methods have been implemented to spatially characterize terahertz(THz)fields.Previous methods usually rely on either specialized THz devices such as THz spatial light modulators or complicated systems requiring assistance from photon-excited free carriers with high-speed synchronization among multiple optical beams.Here,by spatially encoding an 800-nm near-infrared(NIR)probe beam through the use of an optical SLM,we demonstrate a simple sampling approach that can probe THz fields with a single-pixel camera.This design does not require any dedicated THz devices,semiconductors or nanofilms to modulate THz fields.Using computational algorithms,we successfully measure 128×128 field distributions with a 62-μm transverse spatial resolution,which is 15 times smaller than the central wavelength of the THz signal(940μm).Benefitting from the noninvasive nature of THz radiation and sub-wavelength resolution of our system,this simple approach can be used in applications such as biomedical sensing,inspection of flaws in industrial products,and so on.展开更多
基金funded by the US Army Research Office(ARO)(W911NF-17-1-0428)support from the Canada Research Chairs Program and the National Science and Engineering Research Council of Canada.
文摘Recently,computational sampling methods have been implemented to spatially characterize terahertz(THz)fields.Previous methods usually rely on either specialized THz devices such as THz spatial light modulators or complicated systems requiring assistance from photon-excited free carriers with high-speed synchronization among multiple optical beams.Here,by spatially encoding an 800-nm near-infrared(NIR)probe beam through the use of an optical SLM,we demonstrate a simple sampling approach that can probe THz fields with a single-pixel camera.This design does not require any dedicated THz devices,semiconductors or nanofilms to modulate THz fields.Using computational algorithms,we successfully measure 128×128 field distributions with a 62-μm transverse spatial resolution,which is 15 times smaller than the central wavelength of the THz signal(940μm).Benefitting from the noninvasive nature of THz radiation and sub-wavelength resolution of our system,this simple approach can be used in applications such as biomedical sensing,inspection of flaws in industrial products,and so on.
