NLO properties of photonic crystals

Contact Person(s):
Dr. David Gray

Characterization of 3D photonic crystals using z-scan and induced photonic band-gap measurements

Research Topics
Non-linear Spectroscopic Studies


The characterization of 3D photonic crystals is of great importance
in assessing their suitability for application such as high speed all
optical switches. The main techniques that we use for characterization is
(1): the z-scan technique which determines the nonlinear
refractive index change by the change in the focus brought about by
the nonlinearity of the material. The nonlinear absorption is also
(2): photonic band-gap measurements induced by the material's
nonlinearity. Here the material is pumped with an intense laser beam
and a white light source, perpendicular to the pump, is collected
after passing through the crystal. The resulting modification of the
white light is analyzed with a spectrum analyzer to show the shift in
the photonic crystal band-gap.


  • Fabrication of three-dimensional photonic crystal structures containing an active nonlinear optical chromophore
    M. Farsari, A. Ovsianikov, M. Vamvakaki, I. Sakellari, D. Gray, B.N. Chichkov, and C. Fotakis, Applied Physics A, 93, 11, 2008

Project Members
Dr. David Gray
Dr. Maria Farsari

Last Updated:  10/11/2009