Biomolecules and nanostructures
The Optical Sciences group studies the interaction of light and matter. Our current focus is on detection and sensing/imaging with an emphasis on the development of integrated photonics. We are part of Twente University's Department of Science and Technology and member of the MESA+ institute.
Observation of nonlinear bands in near-field scanning optical microscopy of a photonic-crystal waveguide(full pdf)
A. Singh, G. Ctistis, S. R. Huisman, J. P. Korterik, A. P. Mosk, J. L. Herek, and P. W. H. Pinkse
Journal of Applied Physics
Vol. 117 p. 033104 jan. 20 2015
We have measured the photonic bandstructure of GaAs photonic-crystal waveguides with high resolution in energy as well as in momentum using near-field scanning optical microscopy. Intriguingly, we observe additional bands that are not predicted by eigenmode solvers, as was recently demonstrated by Huisman et al. [Phys. Rev. B 86, 155154 (2012)]. We study the presence of these additional bands by performing measurements of these bands while varying the incident light power, revealing a non-linear power dependence. Here, we demonstrate experimentally and theoretically that the observed additional bands are caused by a waveguide-specific near-field tip effect not previously reported, which can significantly phase-modulate the detected field.