At the Lawrence Berkeley National Laboratory, scientists have created microscopic lasers that may end up being used for imaging inside the body, control of biological activity via optogenetics, and performing novel biological studies on living specimens. The lasers, which are about 5 microns in diameter, smaller than red blood cells, turn infrared light into coherent blue and near-infrared laser light.
They’re made of polymer nanoparticles mixed with sodium yttrium fluoride nanoparticles doped with thulium. Though they were expected to “upconvert” light from a lower to a higher frequency, the particles unexpectedly demonstrated the ability to lase at specific wavelengths.
The researchers have already shown that the new nanolasers can work in biological fluids, which means that they have great potential in lifescience research.
A scanning electron micrograph image (left) of a 5-micron-diameter polystyrene bead that is coated with nanoparticles, and a transmission electron micrograph image (right) that shows a cross-section of a bead, with nanoparticles along its outer surface. The scale bar at left is 1 micron, and the scale bar at right is 20 nanometers. (Credit: Angel Fernandez-Bravo, Shaul Aloni/Berkeley Lab)
Study in Nature Nanotechnology: Continuous-wave upconverting nanoparticle microlasers…
Via: Berkeley Lab