title: Unravelling nonlinear spectral evolution using nanoscale photonic near-field point-to-point measurements.
abstract: We demonstrate nanoscale photonic point-to-point measurements characterizing a single component inside an all-optical signal-processing chip. We perform spectrally resolved near-field scanning optical microscopy on ultrashort pulses propagating inside a slow light photonic crystal waveguide, which is part of a composite sample. A power study reveals a reshaping of the pulse's spectral density, which we model using the nonlinear Schrödinger equation. With the model, we are able to identify the various physical processes governing the nonlinear pulse propagation. Finally, we contrast the near-field measurements with transmission measurements of the complete composite sample to elucidate the importance of gaining local information about the evolution of the spectral density.
authors.affiliation: Center for Nanophotonics, FOM Institute AMOLF , Science Park 104, 1098 XG, Amsterdam, The Netherlands.
authors.forename: Matthias
authors.initials: M
authors.lastname: Wulf
authors.forename: Daryl M
authors.initials: DM
authors.lastname: Beggs
authors.forename: Nir
authors.initials: N
authors.lastname: Rotenberg
authors.forename: L
authors.initials: L
authors.lastname: Kuipers
mesh_terms: D003460:Crystallization; D008027:Light; D008962:Models, Theoretical; D036103:Nanotechnology; D017711:Nonlinear Dynamics; D017785:Photons; D012542:Scattering, Radiation