Light can be stopped.

In 1999, Lene Hau, a professor of physics at Harvard, slowed the speed of the light from 186,282 miles per second to 38 miles per hour by passing a beam of light through a small cloud of atoms cooled to temperatures a billion times colder than those in the spaces between stars; two years later, she and her team finally brought the light to a complete stop.  Recently, scientists in Germany have succeeded in stopping light for a whole minute, smashing earlier records; they used a technique called electromagnetically induced transparency.

Light is really fast; at full pelt, it can normally travel more than 20 round trips to the moon in one minute; therefore, stopping the light for one minute is really difficult work, and this can be a major milestone for modern technology. Thomas Halfmann,Christian Hubrich, and Georg Heinze, the scientists who stopped the light for one minute, also they used the same technique to store and then retrieve an image consisting three stripes. Basically Halfmann and his colleagues fired a control laser beam at an opaque crystal, triggering a quantum reaction that turned the crystal transparent. Then they directed a second light source at the now-transparent crystal. The control laser was then turned off, turning the crystal opaque. The light from the secondary source remained trapped inside the crystal, and through multiple trials, the team was then able to extend the period of time in which the light remained halted within the crystal until they reached the record-breaking minutes; however, their current material is close to its physical limit, so they would need other crystal in order to achieve longer light storage times.

This development interests me so much because they basically did the impossible thing; light is the fastest thing in the world, and scientists were able to make the light stops though it’s not permanent. Also, according to this article, if this research gets further light-based improvement, then it could make it possible to store data within beams of light, which could then be sent over long distances. It could also give experts clues on accelerating light beyond the universal speed limit.

So what is the significance of storing data within beams of light? It means, if we further improve this technology, we can set up Quantum Network, a technology that uses the optic’s quantum property that makes impossible to hack, and it can farther reach longer with faster speed. Today, we try to establish Quantum Network by using optic fiber; however, there is a limit of communication distance, and when it’s over 100km, it cannot guarantee enough safety and communication speed, so if we can actually put data into a beam of light, it results a longer communication distant with high safety that we don’t have to worry about hacking while sending an information.

Also, if we can keep the light into a crystal, then we can probably save energy. Since we use electricity to provide light to people other than sunlight, if we can store light into those crystal, we can probably use it instead of light bulb; this will save huge amounts of energy that’s spent on producing the light, and we can use that energy to something else. Therefore, people will not need as much as energy than before, and we can probably stop some of the nuclear power plants, and it would be much safer.

Last thing this improvement will give us is the clue to accelerate the light; by Albert Einstein’s theory of relativity, there is nothing that’s faster than the light. Scientist made a hypothesis about Tachyonic particle, which always moves faster than light. However, its mass is imaginary number, and finding Higgs Boson indirectly proves that there is no Tachyon material at least in this universe.  However, if we can slow and even stop the light, there can be a way to accelerate the light. We can make the light goes faster than the universal limit, which can lead us to time travel.