TY - JOUR AU - NISAR, Muhammad Shemyal AU - CUI, Yujun AU - DANG, Kaitong AU - JIANG, Liyong AU - ZHAO, Xiangwei PY - 2020 TI - Near-Field Spot for Localized Light-Excitation of a Single Fluorescent Molecule JO - Photonic Sensors SN - 1674-9251 SP - 364 EP - 374 VL - 10 IS - 4 AB - Zero-mode waveguides have become important tools for the detection of single molecules. There are still, however, serious challenges because large molecules need to be packed into nano-holes. To circumvent this problem, we investigate and numerically simulate a novel planar sub-wavelength 3-dimension (3D) structure, which is named as near-field spot. It enables the detection of a single molecule in highly concentrated solutions. The near-field spot can produce evanescent waves at the dielectric/water interface, which exponentially decay as they travel away from the dielectric/water interface. These evanescent waves are keys for the detection of fluorescently tagged single molecules. A numerical simulation of the proposed device shows that the performance is comparable with a zero-mode waveguide. Additional degrees-of-freedom, however, can potentially supersede its performance. UR - https://doi.org/10.1007/s13320-020-0593-2 DO - 10.1007/s13320-020-0593-2