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BOB HIRSHON (host):
Shrinking see-through scanners. I’m Bob Hirshon and this is Science Update.
High-frequency terahertz waves can create sharp images of concealed objects, without the dangerous ionizing radiation of x-rays. But until now, they’ve required bulky, expensive equipment in carefully controlled environments. Now, Cal Tech electrical engineer Ali Hajimiri and his colleagues have found a way to generate a powerful terahertz signal from a microchip. It involves coordinating the chip’s many transistors.
ALI HAJIMIRI (California Institute of Technology):
We came up with a way of making these transistors work in concert, together, each one of them contributing a little bit, but overall, collectively, they can generate and radiate the power.
HIRSHON:
Hajimiri says terahertz waves are not only a better and safer alternative to x-rays, but they also have other applications, like detecting cancer cells and chemical traces of bombs or drugs. I’m Bob Hirshon for AAAS, the Science Society.
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