The phase function of optical fields collapse on focusing regions generating a discontinuity in the amplitude function, this induces sources or sinks that corresponds with the topological charge. When the previous comments are transferred to the Plasmon optics context, the discontinuity of the electromagnetic field generates a real distribution of electric charge. This distribution has associated a geometry which can be obtained from the boundary condition of the field. A dynamical character can be implemented on the charge distribution using partial coherence processes in the illumination configuration for the synthesis of the Plasmon field, generating local current distributions modifying selectively the electromagnetic field properties. The model is performed using as a prototype the interaction between plasmon fields Pearcey and Airy kind. Both of them have associated a catastrophe function to the phase function, this mathematical representation allows us to identify and quantify the discontinuity of the electromagnetic field. The computational simulations show that the charge/current distributions present non-linear effects, which offers applications for tunable spectroscopy, plasmonic tweezers, etc.

Date Published: 17 September 2016
PDF: 8 pages
Proc. SPIE 9921, Plasmonics: Design, Materials, Fabrication, Characterization, and Applications XIV, 99213E (17 September 2016); doi: 10.1117/12.2238085

Published in SPIE Proceedings Vol. 9921:
Plasmonics: Design, Materials, Fabrication, Characterization, and Applications XIV
Satoshi Kawata; Din Ping Tsai, Editor(s)