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During the school, the students presented their projects and/or
results at two poster sessions. The level of these two session was at an
outstanding high level both in terms of the scientific content and the
presentations themselves. Therefore, the jury consisting of Prof. S. Jacques,
Prof. K. König, Prof. J. Moan, Prof. S. Andersson-Engels and Dr. P. E. Andersen
had to make a difficult decision. However, everybody on the jury
agreed that the winner had
made a significant scientific contribution as well as an outstanding
presentation. The prize consisted of a diploma and the
book "On Tycho's Island" by J. R. Christianson (Cambridge Univ.
Press, 2000).
The Best Poster Award was awarded to
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Abstract:
Optical forces allow us to trap and manipulate microscopic particles for a
multitude of purposes. In optical tweezing small microscopic particles are
drawn to the highest intensity region of a light beam where they are held by
the light and can be manipulated by moving the beam. This methodology can be
applied to exciting studies in biology including measuring the elasticity of
DNA and blood cells, manipulating chromosomes and studies of molecular motors.
For advanced future studies novel light beams and extended trapping patterns
hold the key to achieving the next generation of results. Bessel beams can be
used to create more complex tweezing systems. Bessel beams are light beams
whose wave vectors lie on a cone, this property means that the beam does not
undergo diffractive spreading as it propagates and also that it can
self-regenerate after an obstacle is placed in its path. Using these
properties it has been possible to trap and manipulate a number of different
particles simultaneously at different points along the beam. Bessel beams have
applications in biological guiding and creating arrays of biological material.
These and other complex light beams can be created using glass holograms made
using microfabrication techniques to etch patterns onto the glass. However, a
spatial light modulator (SLM) is a device that allows us to create and
dynamically control new, more complex, light fields without the need for
microfabrication. An SLM consists of an array of liquid crystals, each of
which can be individually addressed so as to allow us to sculpt or tailor any
light beam hitting its surface. As such we can create novel light beams in a
much simpler manner than before. This potentially offers a new level of
control, allowing us to manipulate and manoeuvre biological matter in a manner
not previously seen.
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