London (UK) - A report published by the Imperial College London and the University of Neuchatel (Switzerland) in the journal Nature Materials says that researchers have demonstrated an effect that solid material can become transparent when hit by a laser.
So far, the effect only work in lab conditions with a very specific material, but the researchers believe that the technology one day could replace x-rays and ultra sound and even see through thick walls and rubble.
According to the article, researchers created "specially patterned crystals" that measured just a few nanometers in length that behaved like "artificial atoms." When hit with a laser, the light did not get absorbed, but entangled with the crystals at a molecular level instead. As a result, the material became transparent.
This new transparent material created by the combination of light and crystals is made up of molecules that are half matter and half light.
The finding challenges one of Albert Einstein's theories that a functional laser requires what is known as "population inversion." The term refers to the condition of the atoms within the light-amplifying material of the laser - typically crystal or glass: Atoms need to be charged with enough energy to allow them to emit light rather then absorb it.
The research, however, shows that light apparently can be amplified without population inversion in a solid material. According to the researchers, quantum physicists have been believed for some time that this was possible, but have not been able to show this effect in materials other than gases.
"This real life "x-ray specs" effect relies on a property of matter that is usually ignored - that the electrons it contains move in a wave-like way" explained Professor Chris Phillips of the Imperial College London. "What we have learned is how to control these waves directly. The results can be pretty weird at times, but it's very exciting and so fundamental. At the moment the effect can only be produced in a lab under specific conditions but it has the potential to lead to all sorts of new applications." Phillips believes that the effect will be able to be reproduced using other, non-specific, materials. For example, he mentioned that future ables could render whole portions of the human body transparent and provide visual access to structures that are hidden behind bones today.
The two universities also discovered an effect that the material created can slow down the speed of light and potentially could even stop it completely. According to Phillips, this could enable scientists to trap and "store" light within the material - which could lead the way to more secure data networks. "When we send information, for example by sending light pulses down optical fibers, it can only be accessed by making a form of measurement, and these measurements always disturb the information," he said. The new technology holds the potential to send light signals without interference: "Now, if confidential information is being spied on, the disturbance shows up right away and we can nab the eavesdropper with 100% certainty," he said.
