Scientists Create Laser No Bigger Than A Single Grain Of Rice
It sounds like something straight out of science fiction: a laser no bigger than a grain of rice that uses one-billionth of the electric current needed to power a hair dryer.
But researchers at Princeton University have created just such a device–and they say it represents a big step forward for quantum computing.
“It is basically as small as you can go with these single-electron devices,” Dr. Jason Petta, a professor of physics at the university and the leader of the team that built the laser, said in a written statement.
To create the microwave laser, or “maser,” Petta and his colleagues used thin nanowires to link up pairs of quantum dots–artificial molecules made up of bits of a semiconductor material called indium arsenide.
Then they placed two of these “double quantum dots” six millimeters apart inside a small cavity made from superconductor material, called niobium, with mirrors on either side.
When the experimental device was hooked up to a battery, electrons flowed through the quantum dots. As the electrons transitioned from a higher energy state to a lower one, they emitted photons in the microwave range. These particles of light bounced off the mirrors to produce —> Read More Here