Metamaterial Holds Key to Controlling THz Radiation

If you’re of my generation, you might remember X-ray Spex. No, not the punk band from the mid-1970s—I’m older than that, alas—but the funky looking glasses advertised in the back of comic books that promised to fulfill every 14-year-old heterosexual boy’s fantasy: to see through women’s clothing. That blast from the past came to mind as I was reading about research on terahertz radiation at Boston University (BU) that may enable us to peer through clothing, walls and human flesh. The research will be discussed at the Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS: 2010), which takes place 16 to 21 May in San Jose, California, USA.

Led by BU’s Richard Averitt, the team has developed a new way to detect and control terahertz (THz) radiation using optics and materials science, reports www.scienceblog.com. This type of radiation is made up of electromagnetic waves that can pass through solid materials without damaging them. The research may pave the way for safer medical and security scanners, new communication devices and more sensitive chemical detectors.

The use of  “metamaterials” by Averitt and his colleagues may clear the stumbling block that historically has thwarted efforts by researchers to effectively manipulate the properties of THz beams.

Metamaterials are unusual in the way they interact with light, giving them properties that don’t exist in natural materials. They have grabbed headlines and captured the popular imagination in recent years after several groups of researchers have used metamaterials to achieve limited forms of “cloaking” — the ability of a material to completely bend light around itself so as to appear invisible. Researchers also recently used metamaterials to produce tiny antennae that may have applications in wireless in vivo devices.

Averitt uses metamaterials to interact with and change the intensity of a beam of THz radiation. His device consists of an array of split-ring-resonators — a checkerboard of flexible metamaterial panels that can bend and tilt. By rotating the panels, his team can control the electromagnetic properties of a beam of THz energy passing by them.

Presentation CtuF3, “Structurally Reconfigurable Metamaterials at Terahertz Frequencies,” by Hu Tao and Richard D. Averitt takes place at CLEO/QELS: 2010 on 18 May at 8:30. Find out more about the technology on the Science Blog.

Tags: averitt, metamaterials, Terahertz, THz