Microsphere-Aided Super-Resolution Scanning Spectral and Photocurrent Microscopy for Optoelectronic Devices

摘要

Dielectric microspheres naturally possess unique optical properties by whichthe light’s focus and confinement can be manipulated on a microscale.Combining microspheres and optical or Raman microscopy, super-resolutionimaging beyond the diffraction limit and enhancement of Raman signals aredemonstrated to provide abundant spectroscopic information on materials.However, microsphere-aided super-resolution scanning photocurrent imagingremains challenging to date. Here, based on the photonic nanojetmechanism, a super-resolution photocurrent and spectral microscopyequipped with a scanning tip with silica dielectric microspheres are presented.With such microsphere-aided microscopy, order of magnitude enhancementsfor single-point Raman and photoluminescence signals can be achieved, andthe spatial resolutions for photocurrent and spectral mapping surpass thebest resolution of the original confocal system restricted by the diffractionlimit. This versatile system enables correlative super-resolution spectral andphotocurrent imaging, serving as a reliable tool for comprehensivelyunderstanding and uncovering the optoelectronic properties of materials.