LIGHT travelling through a solid has been stopped in its tracks for more than a second. This is a thousand times longer than the previous record set in gases.
To stop light in a gas, physicists use a “coupling” laser to nudge the atoms of the gas into a special quantum state that prevents the atoms from interacting with the light. Lower the intensity of the coupling laser, and light pulses travelling through the medium can be slowed down and even halted. Raise the laser’s intensity and the light starts moving again. However, the difficulty in maintaining the quantum state had meant that light could be stopped for less than a millisecond.…
