Darmstadt 2008 – wissenschaftliches Programm
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Q: Fachverband Quantenoptik und Photonik
Q 23: Photonik II
Q 23.2: Vortrag
Dienstag, 11. März 2008, 16:45–17:00, 2B/C
Optical properties of three-dimensional photonic quasicrystals and their periodic approximants — •Alexandra Ledermann1, Costanza Toninelli2, Diederik S. Wiersma2, Martin Wegener1, and Georg von Freymann1 — 1Institut für Nanotechnologie, Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft, DFG-Center for Functional Nanostructures (CFN) and Institut für Angewandte Physik, Universität Karlsruhe (TH) — 2European Laboratory for Nonlinear Spectroscopy (LENS) and INFM, Firence
Quasicrystals (QC) represent a class of solids which lack translational symmetry, but exhibit perfect long-range order and reveal well-defined rotational symmetries, not necessarily consistent with periodicity.
Using direct laser writing [1] we fabricate three-dimensional icosahedral SU-8 photonic QCs of high quality [2] and their so-called periodic approximants [3]. The optical properties of both QC and approximants are studied experimentally and show good agreement with corresponding simulations for the approximants. Time-resolved pulse propagation studies reveal the strongly diffracting character of QC which causes a strong delay and pulse reshaping during the propagation.
This work is an important step towards a better understanding of the effects of quasiperiodicity.
[1] M. Deubel et al., Nature Materials, 3, 444 (2004).
[2] A. Ledermann et al., Nature Materials, 5, 942 (2006).
[3] C. Janot, Quasicrystals- A Primer, Clarendon, Oxford (1992).