What’s the difference between an atomic clock and an optical lattice clock?
Actually, several new technologies are in the running to improve high-performance timekeeping. Traditional atomic clocks (if one can consider a technology developed in the 1940s to be “traditional”) rely on atomic transitions in the microwave region of the electronic spectrum. More recently, scientists are studying clocks based on transitions in the optical regime, where frequencies are higher.
Some optical clocks are based on a single supercooled atom, but the optical lattice clock uses a cloud of atoms confined in a regular “lattice,” sort of like a bunch of marbles on a sheet of egg-crate foam. The more atoms, the more accuracy, at least up to a point.
The Japanese physicist who developed the notion of the optical lattice clock a decade ago, and his colleagues at the University of Tokyo, have come up with a way to make such timekeepers more stable. Read about it in my article on the OPN website.