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Humans tame light, stop it from moving for a full minute

Humans tame light, stop it from moving for a full minute

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Beams of light are usually speeding along at around 186,000 miles per second, but for one minute, researchers in Germany brought some to a screeching halt. Using a crystal frozen to temperatures below negative 450 degrees Fahrenheit, a research team managed to hold light in place for a full minute — marking a drastic increase from the previous record of just 16 seconds. The technology will eventually be applied to quantum computing as a way to retrieve and read data, but it'll have to work on a much smaller scale and for much longer periods of time before that can happen.

Lasers and a super-cold crystal

To allow the opaque crystal to hold light, researchers from the University of Darmstadt first created a small transparency within it that light could enter through, reports New Scientist. The transparent region was held open using a laser beam, but once the stored light had entered the crystal, the laser was shut off. This once again made the crystal fully opaque, giving the light nowhere to go. But importantly, the light wasn't simply absorbed by the crystal as it would when hitting a wall — it stayed put and could still be seen and read.

To release the light, the researchers again opened a transparency in the crystal using a laser. From there, they could measure the particles that were released, and therefore read any information that was being carried away. One of the images of light that the team stored and retrieved featured three horizontal stripes (which can be viewed below). The stripes became less readable the longer they remained within the crystal, but the team was still able to measure their presence after a full 60 seconds had gone by.


The previous record for stopping light — 16 seconds — was set earlier this year, but it came over a decade after researchers first managed to slow light down in the first place. The first instance of slowing light came in 1999, when researchers were able to take it down to just 38 miles per hour. And it might not be long before the minute-long record is broken: the Darmstadt research team believes that they actually could have stored light for longer had they used a different crystal — now they just have to try it.