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.

 

Near-field imaging of plasmonic structures


  • Herman Offerhaus - Chair
  • Jincy Jose - Former member


  • Surface Plasmons are quasiparticles that describe the collective oscillation of conduction electrons at the surface of a metal. They can couple strongly with the light resulting in the generation of Surface Plasmon Polaritons (SPP). The coupling of the surface plasmons with the light requires the matching of the incident photon momentum to the plasmon momentum. For this matching, either a prism coupling or a grating coupling is employed. We explore and investigate plasmonic structures such as curved gratings and nano-antennas that efficiently generate intense (localized) plasmon fields. A phase-sensitive Photon Scanning Tunneling Microscope (PSTM) is used to obtain both the topography and the optical amplitude and the phase of the local field on the structure.

    spatial phase across the glass-gold transistion region on sample
    The above figure depicts the evolution of the shift in spatial phase across the glass-gold transition region of a sample due to the generation of SPP on the gold surface.


    Articles

    The following articles have been published regarding this project:

    Enhanced surface plasmon polariton propagation length using a buried metal grating

    (abstract) (full pdf)
    J. Jose, F.B. Segerink, J.P. Korterik, A. Gomez-Casado, J. Huskens, J.L. Herek, and H.L. Offerhaus1
    Journal of Applied Physics
    Vol 109 Issue 6 p064906-1-7 march 21, 2011
    doi:10.1063/1.3562142

    Imaging of surface plasmon polariton interference using phase-sensitive photon scanning tunneling microscope

    (abstract) (full pdf)
    J. Jose, F.B. Segerink, J.P. Korterik, J.L. Herek, H.L. Offerhaus
    Journal of Applied Physics A: Materials Science & Processing
    vol 103 issue 3 jan 6, 2011
    doi:10.1007/s00339-010-6230-y

    Near-field observation of spatial phase shifts associated with Goos-Hänschen and Surface Plasmon Resonance effects

    (abstract) (full pdf)
    J. Jose, F. B. Segerink, J. P. Korterik and H. L. Offerhaus
    Optics Express
    Vol. 16, No. 3 p.1958 - 1964 jan 28, 2008

    Creating Focused Plasmons by Noncollinear Phasematching on Functional Gratings

    (abstract) (full pdf)
    H. L. Offerhaus, B. van den Bergen, M. Escalante, F. B. Segerink, J. P. Korterik, and N. F. van Hulst
    Nanoletters
    Vol. 5, No. 11 p 2144-2148 oct 19 2005