AN ATOMIC clock could soon be shrunk to the size of a sugar cube, promising an era in which highly accurate clocks will become available in consumer devices, including computers, watches, cellphones and GPS satellite navigation receivers.
Until now, the smallest portable atomic clock was the size of a shoebox, including its battery. At the heart of such clocks is a large glass chamber containing caesium vapour. When excited by a beam of microwaves, the caesium atoms oscillate at a precisely known rate, close to 9.2 billion times per second. By counting these “ticks”, an atomic clock is able to…
