Before the invention of the transistor, telephone switching stations clicked with the sound of small metal arms gating the flow of electricity. A new invention revives mechanical systems, but on a far smaller scale.
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German researchers have come up with a device that takes control of electricity by shuttling electrons across a gap with metronome-like regularity. The mechanism has potential uses in electronic odor detectors and extremely accurate current gauges. A team including Artur Erbe and Robert H. Blick of the Ludwig-Maximilians University in Munich reports its findings in the Aug. 27 Physical Review Letters.