An
international team of plasmonics researchers has developed a novel type
of nanoantenna that could one day lead to advances in security
applications for the detection of drugs and explosives.
A
report of the finding, authored by Swinburne University’s Professor
Saulius Juodkazis and Dr Lorenzo Rosa with a collaborator from China,
has been published in the scientific journal Physica Status Solidi:
Rapid Research Letters.
Nanoantennas
work in much the same way as regular antennas, except they collect
light instead of radio waves and are millions of times smaller.
The
reason that Professor Juodkazis’ nanoantennas are so unique is that
they are fractal – that is they consist of repeating patterns, with the
shape of the smallest feature replicated to make identical, yet larger
structures.
“Self-replication
is an interesting design that is often found in nature. For example,
you will see it on some sea shells,” he said.
This
fractal approach means that the researchers’ nanoantennas can be scaled
down to a very small size, or scaled up to be the width of a human hair
– which in nanophotonics terms is extremely large.
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“Once
we have the smallest bit fabricated there are no restraints, we can
just replicate it and make it larger,” Professor Juodkazis said. “This
is something that has been very difficult to achieve up until now. If
scientists wanted a larger structure, they would just have to fabricate
one.”
“In
a sense we have been able to create a customisable nanoantenna that can
be used for different applications, making it a very cost effective
structure.”
This
new type of nanoantenna has many potential applications, such as the
development of new types of drug and explosives detection kits.
“The
different chemicals found in drugs and explosives are detectable at
very specific wavelengths. Nanoantennas are able to recognise these, and
in turn identify specific types of drugs and explosives,” Professor
Juodkazis said.
While
he is pleased with the developments to date, he expects he will be able
to extend his nanoantenna research even further when Swinburne’s new
plasmonics lab is completed in late 2011.