Counting On Tiny Atomic Clocks

Every mobile device needs to know the time down to the quadrillionth of a second. Atomic physics is making that possible, reports TheFeature.com.

"Most clocks that we check throughout the day are wrong. For example, your wristwatch -- whether it's a Swatch or a Rolex -- probably drifts at least a few seconds each week. Of course, that's probably imperceptible even if you're so overbooked that every second counts. However, wireless technologies are even more tightly scheduled than you are. Indeed, outfitting mobile devices with clocks that are accurate to the quadrillionths of a second could ratchet up cell phone reliability and GPS accuracy while packing more signals into the dwindling radio spectrum.

That's why scientists are developing tiny clocks that are stable to one part in 10 billion, meaning they lose or gain a maximum of just one second every 300 years. These "chip-scale atomic clocks," not much bigger than a grain of rice, count on the natural vibrations of atoms to keep wireless signals on time.

Cellular networks are synchronized according to atomic clocks mounted on the base stations.

The problem is that even the smallest atomic clocks, designed for the cell towers, are still the size of a deck of cards, cost thousands of dollars, and guzzle several watts of power.

Recently though, NIST physicist John Kitching and his colleagues at NIST unveiled the key component in a microscale atomic clock that in a few years could be mass-produced the same way microchips are cranked out in bulk".

emily | 1:07 PM | Technology |
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