Infrared(IR) optics have garnered significant attention due to growing demands in advanced optical imaging,communication, detection, and sensing. Among various IR devices, microlenses and microlens arrays offer distin...Infrared(IR) optics have garnered significant attention due to growing demands in advanced optical imaging,communication, detection, and sensing. Among various IR devices, microlenses and microlens arrays offer distinct advantages in integration capability, imaging precision, multifunctionality, and cost-effective manufacturing. We present a novel design of high-resolution achromatic microlens in the mid-IR region. Different from traditional high-refractive-index convex microlenses embedded within a low-index background medium, the current design is a low-index air concave microlens embedded within a high-index silicon medium. The designed air microlens exhibits capabilities in high-resolution imaging(~λ/6) and achromatic performance across the 3–5 μm mid-IR spectrum. The air microlens could be assembled in large-area microlens arrays or as part of multi-lens system.When combined with the HgCdTe detector system placed on the focal plane, the air microlens can find promising applications in high-resolution optical imaging and high-sensitivity photoelectric detection.展开更多
There has been a long fundamental pursuit to enhance and levitate the Raman scattering signal intensity of molecule by a huge number of~1415 orders of magnitude,to the level comparable with the molecule fluorescence i...There has been a long fundamental pursuit to enhance and levitate the Raman scattering signal intensity of molecule by a huge number of~1415 orders of magnitude,to the level comparable with the molecule fluorescence intensity and truly entering the regime of single-molecule Raman spectroscopy.In this work we report unambiguous observation of single-molecule Raman spectroscopy via synergic action of electromagnetic and chemical enhancement for rhodamine B(RhB)molecule absorbed within the plasmonic nanogap formed by gold nanoparticle sitting on the twodimensional(2D)monolayer WS_(2)and 2 nm SiO_(2)coated gold thin film.Raman spectroscopy down to an extremely dilute value of 10^(18)mol/L can still be clearly visible,and the statistical enhancement factor could reach 16 orders of magnitude compared with the reference detection sample of silicon plate.The electromagnetic enhancement comes from local surface plasmon resonance induced at the nanogap,which could reach~1011 orders of magnitude,while the chemical enhancement comes from monolayer WS_(2)2D material,which could reach 45 orders of magnitudes.This synergic route of Raman enhancement devices could open up a new frontier of single molecule science,allowing detection,identification,and monitor of single molecules and their spatialtemporal evolution under various internal and external stimuli.展开更多
基金supported by the Science and Technology Project of Guangdong Province, China (Grant No. 2020B010190001)the National Natural Science Foundation of China (Grant No. 12434016)the National Key Research and Development Program of China (Grant No. 2018YFA0306200)。
文摘Infrared(IR) optics have garnered significant attention due to growing demands in advanced optical imaging,communication, detection, and sensing. Among various IR devices, microlenses and microlens arrays offer distinct advantages in integration capability, imaging precision, multifunctionality, and cost-effective manufacturing. We present a novel design of high-resolution achromatic microlens in the mid-IR region. Different from traditional high-refractive-index convex microlenses embedded within a low-index background medium, the current design is a low-index air concave microlens embedded within a high-index silicon medium. The designed air microlens exhibits capabilities in high-resolution imaging(~λ/6) and achromatic performance across the 3–5 μm mid-IR spectrum. The air microlens could be assembled in large-area microlens arrays or as part of multi-lens system.When combined with the HgCdTe detector system placed on the focal plane, the air microlens can find promising applications in high-resolution optical imaging and high-sensitivity photoelectric detection.
基金supported by the National Natural Science Foundation of China(11974119)Science and Technology Project of Guangdong(2020B010190001)+1 种基金Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06C594)National Key R&D Program of China(2018YFA 0306200).
文摘There has been a long fundamental pursuit to enhance and levitate the Raman scattering signal intensity of molecule by a huge number of~1415 orders of magnitude,to the level comparable with the molecule fluorescence intensity and truly entering the regime of single-molecule Raman spectroscopy.In this work we report unambiguous observation of single-molecule Raman spectroscopy via synergic action of electromagnetic and chemical enhancement for rhodamine B(RhB)molecule absorbed within the plasmonic nanogap formed by gold nanoparticle sitting on the twodimensional(2D)monolayer WS_(2)and 2 nm SiO_(2)coated gold thin film.Raman spectroscopy down to an extremely dilute value of 10^(18)mol/L can still be clearly visible,and the statistical enhancement factor could reach 16 orders of magnitude compared with the reference detection sample of silicon plate.The electromagnetic enhancement comes from local surface plasmon resonance induced at the nanogap,which could reach~1011 orders of magnitude,while the chemical enhancement comes from monolayer WS_(2)2D material,which could reach 45 orders of magnitudes.This synergic route of Raman enhancement devices could open up a new frontier of single molecule science,allowing detection,identification,and monitor of single molecules and their spatialtemporal evolution under various internal and external stimuli.
