August 16, 2018
A microscopic trampoline could help engineers to overcome a major hurdle for quantum computers, researchers from the University of Colorado Boulder (CU Boulder) and the National Institute of Standards and Technology (NIST) report in a new study.
Robert Peterson, a former graduate student at JILA, works with a "dilution refrigerator." This equipment can cool scientific instruments, like a new quantum "trampoline," down to a fraction of a degree above absolute zero. Credit: Peter Burns.
Scientists at JILA, a joint institute of CU Boulder and NIST, have developed a device that uses a small plate to absorb microwave energy and bounce it into laser light—a crucial step for sending quantum signals over long distances.
Graduate student Peter Burns said that his team’s research could one day help engineers to link together huge networks of quantum computers.
Over the last decade, several tech firms have made inroads into designing prototype quantum chips, which have the potential to be much more powerful than traditional computers. But getting the information out of such chips is a difficult feat.
One big challenge lies in translation. Top-of-the-line quantum chips like Google’s Bristlecone or Intel’s Tangle Lake send out data in the form of photons, or tiny packets of light, that wobble at microwave frequencies. Much of modern communications, however, relies on fiber-optic cables that can only send visible light.
In research published recently in Nature Physics, the team reports that zapping a small plate made of silicon-nitride with a beam of microwave photons causes it to vibrate and eject photons from its other end. But those photons now quiver at optical frequencies.
According to information, the researchers were able to achieve that hop, skip and a jump at an efficiency of 47 percent, meaning that for every two microwave photons that hit the plate, close to one optical photon came out. That’s a much better performance than other methods for converting microwaves into light, such as by using crystals or magnets, Burns said.