Near-field 3D mapping of spiral light structures formed by a polymer nanocylinder

It is demonstrated that polymer nanocylinders can form spiral light structures. Spiral distributions of light intensity are observed at distances of 230–1100 nm above the nanocylinder with a diameter of 700 nm and a height of 1100 nm. The optical spirals are measured using a scanning near-field optical microscope that performs 3D scanning over planes when the nanocylinder is illuminated from the bottom with linearly polarized CW He-Ne-laser radiation at a wavelength of 632.8 nm. It is shown that the topology of the optical spirals significantly depends on the incident polarization.