Aug 24, 2010 09:29 GMT  ·  By

In a development that could see devices such as quantum computers and quantum cryptography circuits becoming more capable and efficient than eve, researchers developed a new type of optical antenna, that can easily make devices handling small amounts of photons better.

The achievement was reached in Barcelona, Spain, at the Institute of Photonic Sciences. Experts here, led by professor Nick van Hulst, created a nanoscale antenna that can handle photons with extreme efficiency.

The research team says that the new antenna they produced is only a few hundred nanometers in size, and adds that it can only direct light going in a single direction.

When viewed through a high-power microscope, the antenna looks just as a directional TV antenna, considering that it contains five nanoscale gold bars of diminishing length, sitting across one larger bar.

The very reason why this antenna is so advanced is the fact that it can transmit photons in a single direction. Existing components that seek to fulfill the same role transmit in all directions.

“It's very difficult to control where the photons go,” van Hulst says. He adds that the group used the common Yagi-Uda antenna as a source of inspiration for their new device.

“We use exactly the same one used to detect TV signals,” the researcher explains. In order for such structures to work, they need to be tuned to the electromagnetic radiation they have to capture.

In the case of light, this means that the antenna needs to be no larger than a couple hundred nanometers.

According to the science group, of the five bars on the antenna – called elements – only the second one features any kind of electrical contacts.

All the other elements are passive, meant to direct light in a single direction. The components were made using a technology known as electron beam lithography, Technology Review reports.

The team says that the antenna has been tune to the terahertz range, which means that it emits infrared light with a wavelength of 800 nanometers.

This is the “best optical antenna I have seen,” says of the innovation Markus Lippitz, who is based in Stuttgart, Germany, at the Max Planck Institute for Solid State Research.