University
of Toronto
Physics Department
SPECIAL SEMINAR
University
of Toronto
Physics Department
SPECIAL SEMINAR
PLEASE NOTE NON-STANDARD DAY, TIME & LOCATION
| Speaker : |
Professor Ralf Wehrspohn, University of Paderborn |
| Topic : |
3d photonic crystals from macroporous silicon |
| Time : | Friday, August 1, 2003 at 11.00 a.m. |
| Place : | Room MP408, Burton Tower, 60 St. George Street |
Abstract
Ralf Wehrspohn, J.
Schilling. S. Matthias and R.Hillebrand
Two dimensional photonic crystals obtained by photoelectrochemical etching of
macroporous silicon are now well established. However, the same method also
allows to prepared inverse simple hexagonal and simple cubic 3D photonic
crystals. Structural and optical properties of both symmetries are shown and
first results of a realised sc structure are presented which seems to have a
small but complete photonic bandgap as determined by reflection and
transmission. Moreover, the combination of photoelectrochemical etching and
focused ion beam etching allows us to created a hexagonal structure (similar to
the SP2 structure) which is predicted to have a complete photonic bandgap of
25%. First experimental results are shown. Moreover, a new way to infiltrate
local emitter into photonic crystals based on wetting phenomena is introduced.
This allows an exact placing of emitters at the walls inside the pores of a
photonic crystal, an important requirement considering the variation of the LDOS across pores.
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