The core of the new room-temperature maser
When the laser was first invented, it was “a solution waiting for a problem,” a piece of cutting-edge technology with no applications. Today, found in everything from sensors to communications to surgery, the laser has come into its own—but it may be time to step aside and share the spotlight with its older brother, the maser.
Lasers and masers work on the same principle, amplifying light through a process called stimulated emission, except that lasers amplify visible light while masers act on microwaves. Light and microwaves are both forms of electromagnetic radiation, but microwaves have a wavelength 100,000 times greater than that of visible light. But although the maser has been used for deep-space communications and atomic clocks, lasers have always outshone their predecessors. And masers have only themselves to blame, as these finicky devices require extreme conditions like vacuum or cold temperatures. Now, however, researchers have finally produced a maser that functions while surrounded by air at room temperature.
If you’ve ever investigated how a microwave warms up your food, then you already know that the box fills with electromagnetic waves, which vibrate water molecules to create friction and heat. But how does the microwave’s magnetron (an energy-generating vacuum tube) produce those waves in the first place—and how can you measure them using cheese? The Engineer Guy, also known as University of Illinois at Urbana-Champaign professor Bill Hammack, has all the answers in this enlightening video.