Laser Tuner Boosts Radio Reception
It’s happened to all of us. You’re on your cell phone, your boss is saying something important, and then th.. con...ction star..s to dr…p out.
Now a team of physicists in Denmark, led by Albert Schliesser and Eugene Polzik, has demonstrated a new kind of radio tuner that is far more sensitive to faint signals. The technique could eventually mean fewer dropped calls, better GPS coverage, faster Wifi, and much more detailed images from MRI scanners.
The tuner includes a novel component: a tiny reflective membrane just half a millimeter on a side and only a hundred nanometers thick. It functions in the circuit as a capacitor, and when radio waves pass through the antenna, the minuscule voltage shifts make the membrane bounce like a trampoline.
Laser light, reflecting off the membrane and then interfering with itself, turns those nanometer-high wiggles into a strong, clear signal. The report is published on the site arXiv.org. [Tolga Bagci et al., Optical detection of radio waves through a nanomechanical transducer]
The scientists are excited about how the technology might sharpen the pictures produced by radio telescopes. But wouldn’t it also be nice to actually get decent phone reception inside a parking garage?
[The above text is a transcript of this podcast.]