Researchers in Australia have developed new microscopic lasers that have a range of potential medical, surgical, industrial and military uses.   Researchers at the Australian National University (ANU) say “nanolasers” promise to be even more powerful than conventional technology. The technology uses laser light instead of electronics and is an approach called photonics. Nanolasers, they say, need only a small amount of energy to start shining. Instead of using mirrors that reflect light, the team has created a device that traps energy and prevents it from escaping. That power is harnessed and builds into a “strong, well-shaped” beam. Researchers say this overcomes a well-known challenge of nanolasers — “energy leakage.”   The project is a collaboration with academics at Korea University, and is published in the journal Nature Communications. The lead researcher is professor Yuri Kivshar, who says the beams would act like a torch, or flashlight, to guide a surgeon.   “Why do we need [it] smaller? Imagine you are doing [a] kind of operation inside of body [sic] and you are using optical fiber. So, optical fibers introduced inside of body will see only light, which inside there is basically nothing, so you need a kind of torch. This torch will lighten the place which you need to work on and that will be a kind of real torch effect,”  he said.Academics have said that while their nanolasers are not the smallest ever developed, they are among the most efficient and powerful.   According to the ANU study, the energy threshold at which the laser starts to work is about 50 times lower than any previously documented nanolaser.    The physicists believe the technology could have a range of applications in small devices, including hair removal, laser printing, night-time surveillance and the illumination of delicate surgery inside the body.   
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