Invisibility cloak becomes reality

British and Danish experts claim to have successfully built invisibility cloaks, which can hide objects by splitting light.

A piece of string disappeared after "covering" the calcite cloak.

According to a report published in the Nature Communications journal, unlike a real-life shirt like the Harry Potter series, the invention is actually a crystal of calcite, which works to invisible objects like nails. pins and paper clips in the laboratory. Physicists from the University of Birmingham, the Imperial College and the Technical University of Denmark said the crystal allows them to cover larger objects than other methods.

The team of experts, led by Dr. Shuang Zhang, glued two triangular calcite pieces together, above the mirror. Light shines on calcite and is split into two groups of rays, moving at different speeds and directions. Dr. Zhang said that the group's experiments showed that this was the first time the ' cloaked ' area was visible to the naked eye. Thanks to natural crystals, not special metamaterials like meta (capable of controlling electromagnetic radiation), experts were able to stretch the size of the invisibility cloak to cover it. objects larger, thousands of times longer than the wavelength of light.

Previously, some experts also claimed to create invisibility cloaks, but they only covered objects at the micron level (much smaller than human hair thickness). And the prospect of developing invisibility with super metamaterials is very difficult and takes a lot of time. However, with this discovery, scientists can now embark on the construction of a large-size invisibility cloak to serve applications in the near future.