Researchers have shown off a microwave-emitting version of the laser, called a maser, that works at room temperature.
Masers were invented before the laser, but have languished in obscurity because they required high magnetic fields and difficult cooling schemes.
A report in Nature outlines a far simpler version using a crystalline material and no cooling or magnets.
The resulting intense microwave beams could be used in applications ranging from medical diagnostics to astronomy.
Masers were borne of an idea first postulated by Albert Einstein: that in some materials, energy could be pumped in and concentrated into a beam of electromagnetic waves oscillating in synchrony.
The first maser – an acronym of microwave amplification by stimulated emission of radiation – was built in 1953, and later masers were used, for example, in the first transatlantic television broadcast.
But researchers carried the work on, coaxing materials to amplify visible light instead of microwaves, earning three of them the 1964 Nobel prize in physics.
These “lasers” reached complete ubiquity as simple designs for them were perfected and applications for them proliferated…