World's Tiniest Tweezers Grab Nanoparticles Using Nothing But Light

When you're working with tiny nanoparticles, you need extremely delicate tools. Like, say, tweezers that can manipulate particles 1,000 times thinner than a human hair without physically touching them. That's exactly what researchers at the Institute of Photonic Sciences have come up with: optical nanotweezers that use light to move tiny particles in three dimensions. It's not sci-fi anymore.

Optical tweezers have been around since the 1980s, but so far they've only able to trap objects a few hundred nanometers in size—relatively huge by nanotech standards. Further, proof-of-concept devices weren't able to manipulate objects in three dimensions, and the light beams they used ended up overheating the objects they grabbed. Not good.

Now, a group led by Professor Romain Quidant has created an optical tweezer that solves all those problems. Using a metal-coated optical fiber with a bowtie-shaped opening (shown above), the device focuses a beam of laser light in such a way that "self-induced back action" shapes the light to envelop and trap a microscopic object.

The result is the world's first device that can grab a super-tiny 50 nanometer object and move it across distances of several micrometers, without overheating the target object. The device could open up a whole new field of research, where scientists can safely grab and move single molecules or viruses without damaging them, or construct DNA or other structures piece by piece.

If you speak this highly-advanced language, go check out the Nature Nanotechnology research paper the team just published explaining how this all works. It'll definitely grab you. [Nature Nanotechnology via PopSci]

Images via Institute of Photonic Sciences