The phenomenon of superoscillation produces oscillations that are faster than the fastest Fourier component of a system, potentially forming a local “hot spot” with a size below the diffraction limit. We show that a radially polarized Laguerre–Gaussian mode has the inherent ability to form superoscillation spots simply by controlling the incident beam size. We investigate this in detail, both numerically and experimentally. Our numerical simulations predict that lateral resolutions close to 100 nm are possible for practical confocal laser scanning microscopy with visible light. We demonstrate experimentally that superoscillation focusing can offer significant spatial resolution improvements for fluorescence imaging.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics