Quantum timekeeping is supposed to be the ultimate in efficiency, with tiny devices that tick using the rules of quantum mechanics instead of swinging pendulums or vibrating quartz. Yet new work on a ...

Graphic illustrating the difference in energy between running a quantum clock (left: a single electron hopping between two nanoscale regions) and reading the ticks of the clock (right). The energy ...

Today, checking the time is effortless. A quick glance at a wristwatch, a wall clock, or even a mobile phone instantly tells ...