6/22/2023 0 Comments Maser elyoum![]() There is plenty of room for improvement, agrees Oxborrow. In the long term it could find a use in communications, but it first needs to be refined. Oxborrow's device could simplify and improve masers, says Hilsum. "It shows great originality and great ability." "It is a considerable achievement," says Cyril Hilsum, a retired physicist who helped to develop some of the earliest solid-state lasers. Alone in his lab, "I swore a lot and walked around the corridor about five times talking to myself". "The signal that came out of it was huge," says Oxborrow, about a hundred million times as powerful as an existing maser. It was the same principle as an optical laser. Then a microwave passing through the crystal triggered the molecules to relax, releasing a cascade of microwaves of the same wavelength. The laser light excited the pentacene molecules to an energy level known as a metastable state. "I said, 'Oh well, what the hell, let's just try it." And it worked on the first go. Whereas less well-behaved people might have wallowed in the pub, "I went to the lab as a bit of therapy", says Oxborrow. The final impetus came from an argument with his wife. "For about three days, I could have done it, but I didn't have the nerve to switch on that button," he says. Oxborrow admits that he was skittish about the experiment. ![]() But the researchers were filled with doubts - the whole thing seemed too easy. ![]() Oxborrow located an old medical laser on eBay and drove to a warehouse in north London to pick it up. The result was a pink crystal a few centimeters long. He borrowed some spare pentacene from a lab at Imperial, and cooked it with another organic molecule known as p-terphenyl. Oxborrow enlisted two colleagues - materials scientists Jonathan Breeze and Neil Alford from Imperial College London - and got to work on testing this suggestion. He came across a decade-old publication by Japanese researchers suggesting that when the electrons in pentacene are excited by a laser, they configure such that the molecule could work as a maser, possibly even at room temperature. Those masers work only when cooled to less than ten degrees above absolute zero, and even then they are not nearly as powerful as lasers.īut Mark Oxborrow, a physicist at the UK National Physical Laboratory in Teddington, wondered whether a crystal containing the organic molecule pentacene might offer a breakthrough. It found only a few niche uses, such as boosting radio signals from distant spacecraft - including NASA's Curiosity Mars rover. Lasers are now used in applications ranging from eye surgery to CD players. They produced only a few nanowatts of power, severely limiting their usefulness.īecause of this impediment, most in the field gave up on masers and moved on to lasers, which use the same principles of physics, but work with optical light instead of microwaves. First conceived in the Soviet Union and the United States during the 1950s, early maser machines were the size of a chest of drawers. The work is published this week in Nature.īefore there were lasers, there were microwave lasers, or masers. The achievement comes nearly 60 years after the first clunky versions of such devices were built, and could revolutionize communication and space exploration. Using spare chemicals, a laser bought on eBay and angst from a late-night argument, physicists have got the world's first room-temperature microwave laser working.
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