Plasmonic Nanowires Advance Optical Computing

A technique that combines surface plasmons, useful for data transfer, with cold atoms that store data may enable the construction of optical and quantum computing devices.

A Bose-Einstein condensate is applied to plasmonic nanowires. (Images: University of Tübingen)

In the new technique, cold atoms interact with gold nanowires that have been illuminated with laser light to generate surface plasmons. The cold atoms are created by cooling atomic gases in a vacuum chamber to as low as a few hundred nanokelvin, which forms a Bose-Einstein condensate — essentially a single huge super-atom. The condensate can be shifted by external magnetic fields to the surface of the nanowires, where it can be influenced by the plasmons.

The plasmonic structures are integrated into the surface of a prism.

"We can generate plasmons which attract the atoms and others which repel them," said Dr. Sebastian Slama from the University of Tübingen. "By structuring the surface, we can tailor almost arbitrary potential landscapes for the atoms.

"Our goal is to build hybrid devices for optical computing and quantum information. We were now able to set a milestone, but there is still a lot to do," Slama said.

The research was published in Nature Photonics.

For more information, visit: www.uni-tuebingen.de/en