Scientists have used the same technology that brought us time crystals to create a room-temperature maser—a microwave laser—that overcomes many of masers’ past problems.
Masers predate lasers. They’re pretty much the same thing, but masers shoot out microwave light instead of visible or infrared light. Lasers have always been more popular, since masers have only worked in short pulses and required incredibly cold temperatures and vacuums to operate. But now, a team of scientists in the United Kingdom has overcome both old and new challenges to debut their continuously emitting, room-temperature maser. Their research was published this week in Nature.
Masers and lasers operate on basically the same principle. Atoms typically have electrons orbiting their nuclei in specific energy levels. Add some energy in the form of, say, a photon, and the electrons jump to higher energy levels. Pump enough of those electrons into the same higher energy level, and you can release a cascade of photons of the same color (or wavelength, in physics speak) whose waves line up.