Silvia Mittler
Current Research
- Organo Metallic Chemical Vapor Deposition (OMCVD)
- In this current research project both gold and palladium OMCVD precursors are synthesised and used to deposite
ultra thin films of palladium/palladium ions or panecake-shaped gold nanoparticles. The main interest is to use
these new metal structures for binding chemical and biological recognition sites via thiol (-SH) or sulfide bonds.
On the other hand the nucleation and growth process of these new kind of nanoparticles is still not fully understood.
- Gold Nanoparticle Clusters and their Optical Response
- With the help of templates fabricated by laterally nano-structured self-assembled monolayers defined clusters
of gold nanoparticles should be deposited by OMCVD. The optical response in two polarisation direrctions due to cross talk
or other coupling mechanisms should be studied.
- Evanescent Wave Analytical Tools
- Optical slab waveguides and fibres, as well as excited surface plasmons show evanescent fields reaching some hundrets
of nanometers into the space above the device surface. These fields are used to detect chemical and biological reactions,
typically guest-host or recognition reactions right on the surface of these devices.
- Surface Functionalisation
- In order to build a highly specific and highly sensitive sensor using the evanescent fields of an integrated optical
device the surface functionalisation, responsible for the recognition reaction, has to be well engineered. Typically the functionalisations
are formed by monolayers on top of the device offering its chemical or biological function right at the surface.
Those monolayer films can be either fabricated via Langmuir-Blodgett-Kuhn technique or by self-assembling. In both cases
the structure of the film, the functionaliity density and other parameters have to be optimised.
- Detection of Optically Active Molecules
with Means of Integrated Optical Devices
- Optical active material can turn the polarisation direction of a light
beam. The turning strength depends on the concentration, the interaction length
between the light and the material as well as its optical activity, which
shows a dispersion behaviour. In this current project integrated optical devices
will be used to measure the optical activity.
- Optical Tweezers in Evanescent Fields
- The evanescent fields of a channel waveguide acts as an optical tweezer to hold an object on top of itself. On the other hand a momentum
is carried in the evanescent field in the direction of propagation. By using a channel waveguide objects should be tapped on a channel surfaces
and carried forward by laser pulses. The movement should be directely correlated with adhesion forces between the object and the waveguide surface.
Lateral patterning of the entire device surface should allow for defined stops and go's.
- Evanescent Microscopy and Spectroscopy
- With this microscopy and spectroscopy methode in the evanescent field of a waveguide
we can image objects and wiill measure their absorption spectrum polarisation dependent. Typical examles will be the OMCVD
gold nanoparticles and the gold nanoparticle clusters.
Silvia Mittler Home
April 2007
Department of Physics and Astronomy ,
University of Western Ontario
Comments to
smittler@uwo.ca