Researchers Unveil Spaser - World's Tiniest Laser

Researchers from Norfolk State University, Purdue University and Cornell University have unveiled the tiniest laser called the Spaser. Applications including superfast computers, advanced sensors and imaging that are potentially 10 times more powerful that today's could be the result with this new innovation.

Spaser stands for surface plasmon amplification by stimulated emission of radiation.

The Spaser is the first of its kind to emit visible light and represents a critical component for future technologies based on nanophotonic circuitry according to Vladimir Shalaev, the Robert and Anne Burnett Professor of Electrical and Computer Engineering at Purdue University. The findings are detailed in a paper in the journal Nature.

The findings confirm earlier work performed by physicists David Bergman at Tel Aviv University and Mark Stockman at Georgia State University, who first proposed the spaser concept in 2003.

The spasers contain a gold core surrounded by a glasslike shell filled with green dye. When a light is shined on the spheres, plasmons generated by the gold core are amplified by the dye. The plasmons are then converted to photons of visible light, which is emitted as a laser.

The color diagram (a) shows the nanolaser's design: a gold core surrounded by a glasslike shell filled with green dye. Scanning electron microscope images (b and c) show that the gold core and the thickness of the silica shell were about 14 nanometers and 15 nanometers, respectively. A simulation of the SPASER (d) shows the device emitting visible light with a wavelength of 525 nanometers. (Birck Nanotechnology Center, Purdue University)

Nanophotonics circuits will require a laser-light source such as Spaser as current lasers can't be made small enough to integrate them into electronic chips. Nanophotonics devices created using Spaser's could include powerful hyperlenses resulting in sensors and microscopes 10 times more powerful and see objects as small as DNA. Computers and consumer as well solar collectors would also benefit from this innovation.

"Here, we have demonstrated the feasibility of the most critical component - the nanolaser - essential for nanophotonics to become a practical technology," Shalaev said.

Reference:

1. New nanolaser key to future optical computers and technologies, Purdue University