Extended Data Fig. 7: Schematic diagram for the resolution of near-field optical microscopy.
From: Visualizing vibrational normal modes of a single molecule with atomically confined light
a, Local electric field along the z axis, Ez, arising from a charge. Only the z component is considered because in-plane dipoles induced by tangential components are cancelled by their images in the metallic substrate. b, Comparison between the fourth power of the Coulomb field distribution (q = 1) and equivalent Gaussian with the associated FWHM value.
