Shining a light into nano’s uncharted application areas
Everyone knows carbon nanotubes have tremendous potential, but who expected that they might work as flashlights? Answer: IBM researcher Jia Chen. Last year, she published a paper in Science describing a new way to make carbon nanotubes into light sources a thousand times brighter than light-emitting diodes. With this discovery she brings closer a time when all information may be efficiently transmitted using speed-of-light photons rather than relatively pokey electrons.
IBM researcher Jia Chen developed a new way to convert electricity into light using nanotubes. Photo courtesy of IBM
Her research group injected electrons into carbon nanotubes and “tricked” them into picking up positive charges at a faster rate than usual through clever design of the substrate holding the nanotubes. Every time an electron bonds with a positive charge, or “hole,” it produces a photon. The particular technique results in every injected electron producing a photon - a much more efficient rate than usual.
In an article that appeared in Small Times Chen reports, “We were able to coerce the electrons to convert the energy to light instead of dissipating into heat.” And the best part: the photon-emitting nanotubes can be produced using the same fabrication processes as silicon semiconductor devices and potentially can be built into light-based circuitry in the same footprint as conventional electronic components.
The nanotube light isn’t Chen’s first venture into world-changing research. As a graduate student at Yale, working with Mark Reed (longtime collaborator of Innovator of the Year, Jim Tour), she created the first reversible molecular switch. The achievement was chosen for Science’s 2001 “breakthrough of the year” section.
Among numerous accolades, she has also been recognized by the National Academy of Engineering as one of the nation’s top 80 brightest young engineers. She holds U.S. and foreign patents on molecular devices, memory storage devices, CMOS processes and devices, and carbon nanotube electronic and optoelectronic devices.
Russell Cowburn, chair in Nanotechnology, Imperial College London, invented a laser scanning technique that reads the unique nanoscale irregularities in the surface of paper and uses them to track a “fingerprint” to thwart counterfeiters. The fingerprint survives even if the paper is soaked in water, scorched or scrubbed with abrasive pads.
Photo courtesy of Imperial College London
James Tour, Innovator of the Year winner, Chao Professor of Chemistry, and director of the Smalley Institute for Nanoscale Science and Technology at Rice University, is bringing molecular self-assembly to the point of commercial reality. His nanocar is a practical example of molecular manipulation, and his group is working on more sophisticated machines.
Photo courtesy of Rice University
Huikai Xie, assistant professor of electrical and computer engineering, University of Florida, designed a tiny motion sensor that can be manufactured with standard CMOS technology that uses one-thousandth of a watt of power. It has myriad potential applications, including in clothes to track the motions of athletes or to monitor the elderly in their homes.
Photo courtesy of University of Florida
Jie Zhang, principal staff engineer, Motorola, demonstrated the first all-printed timing circuit produced using a graphic arts printing press and nanoscale-particulate-based inks. That was in 2003 and, since then, she has used those techniques to fabricate 50 miles of integrated circuits as well as drive the research to the stage where it’s ready to be produced and commercialized.
Photo courtesy of Motorola