Physicists create worlds smallest switch at molecular level

A team of physicists at the Technical University of Munich have created in their laboratory what they believe to be the world's smallest molecular switch. In their experiment, the team was able to build a switch with an inner diameter of less than half a nanometer, making it making it the smallest atomic switching unit realized to date. It moves a single proton to one of four positions or states at speeds of up to 500 changes in state per second.......

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http://afanley.livejournal.com/1492680.html