CHESTNUT HILL, Mass. (4/15/08) A frequency-agile metamaterial that for the first time can be tuned over a range of frequencies in the so-called terahertz gap has been engineered by a team of researchers from Boston College, Los Alamos National Laboratory and Boston University.
The team incorporated semiconducting materials in critical regions of tiny elements in this case metallic split-ring resonators that interact with light in order to tune metamaterials beyond their fixed point on the electromagnetic spectrum, an advance that opens these novel devices to a broader array of uses, according to findings published in the online version of the journal Nature Photonics.
Metamaterials no longer need to be constructed only out of metallic components, said Boston College Physicist Willie J. Padilla, the project leader. What weve shown is that one can take the exotic properties of metamaterials and combine them with the unique prosperities of natural materials to form a hybrid that yields superior performance.
Padilla and BC graduate student David Shrekenhamer, along with Hou-Tong Chen, John F. OHara, Abul K Azad and Antoinette J. Tayler of Los Alamos National Laboratory, and Boston Universitys Richard D. Averitt formed a single layer of metamaterial and semiconductor that allowed the team to tune terahertz resonance across a range of frequencies in the far-infrared spectrum.
The teams first-generation device achieved 20 percent tuning of the terahertz resonance to lower frequencies those in the far-infrared region addressing the critical issue of narrow band response typical of all metamaterial designs to date.
Constructed on the micron-scale, metamaterials are composites that use unique metallic contours in order to produce responses to light waves, giving each metamaterial its own unique properties beyond the elements of the actual materials in use.
Within the past decade, researchers have sought ways to si
|Contact: Ed Hayward|