Princeton University researchers have built a rice grain-sized microwave laser. Credit: Jason Petta, Princeton University
Princeton University researchers have built a rice grain-sized laser powered by single electrons tunneling through artificial atoms known as quantum dots. The tiny microwave laser, or "maser," is a demonstration of the fundamental interactions between light and moving electrons.
The researchers built the device—which uses about one-billionth the electric current needed to power a hair dryer—while exploring how to use quantum dots, which are bits of semiconductor material that act like single atoms, as components for quantum computers.