Washington: Scientists have developed a new type of nano antenna which collect light instead of radio waves, which they claim could lead to advances in security applications for the detection of drugs and explosives.
Nano antennas 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 the nano antennas are so unique is that they are fractal -- that`s 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," Prof Saulius Juodkazis of Swinburne University, who led the team, said.
This fractal approach means that the nano antennas 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
"Once we have the smallest bit fabricated there are no restraints, we can just replicate it and make it larger. 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 customizable nanoantenna that can be used for different applications making it a very cost effective structure," Prof Juodkazis said.
This new type of nano antenna 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. Nano antennas are able to recognise these, and in turn identify specific types of drugs and explosives," Prof Juodkazis said.
The findings have been published in the `Physica Status Solidi: Rapid Research Letters` journal.
First Published: Saturday, May 07, 2011, 15:25