2014/11/17 by Martin Neugebauer, Thomas Bauer, Andrea Aiello +1 · 3 citations
Engineering · Physics and Astronomy · #Condensed matter physics #Dielectric #Electric field #Excitation #Field (mathematics) #Near-Field Optical Microscopy #Optics #Optoelectronics #Orbital Angular Momentum in Optics #Physics #Plasmon #Plasmonic and Surface Plasmon Research #Quantum mechanics #Solenoidal vector field #Spin (aerodynamics) #Transverse plane #Vector field #physics.optics
paper · pdf · doi:10.1103/physrevlett.114.063901
published as Phys. Rev. Lett. 114, 063901 (2015) · 5 pages, 3 figures
arxiv created 2014/11/17 · openalex publication_date 2015/02/09 · arxiv updated 2015/03/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We generate tightly focused optical vector beams whose electric fields spin around an axis transverse to the beams' propagation direction. We experimentally investigate these fields by exploiting the directional near-field interference of a dipolelike plasmonic field probe placed adjacent to a dielectric interface. This directionality depends on the transverse electric spin density of the excitation field. Near- to far-field conversion mediated by the dielectric interface enables us to detect the directionality of the emitted light in the far field and, therefore, to measure the transverse electric spin density with nanoscopic resolution. Finally, we determine the longitudinal electric component of Belinfante's elusive spin momentum density, a solenoidal field quantity often referred to as "virtual."