Researchers have succeeded in developing an extremely thin invisibility cloak that can adapt itself to the shape of any three-dimensional object and mask it from detection in visible light. Although this cloaking cloak currently only exists in a microscopic size, the principles underlying the technology could allow it to be extended to the disappearance of macroscopic objects as well.
![The image depicts a three-dimensional illustration of the disappearance cloak of a metasurface consisting of an ultra-thin layer of nano-antennas (gold particles) that masks the underlying bone. The light is deflected out of the surface of the cloak (red arrows) as it would be deflected by a flat mirror. [Courtesy: Xiang Zhang group, Berkeley Lab/UC Berkeley]](https://www.hayadan.org.il/images/content3/2015/09/Xiang-Zhang-image-for-cloak1-500x388.jpg)
Researchers have succeeded in developing an extremely thin invisibility cloak that can adapt itself to the shape of any three-dimensional object and mask it from detection in visible light. Although this cloaking cloak currently only exists in a microscopic size, the principles underlying the technology could allow it to be extended to conceal macroscopic objects as well.
Invisibility cloaks are a nice idea drawn from the worlds of science fiction and fantasy, from the Star Trek film series to Harry Potter, but they don't exist in reality, or do they? Scientists from the Lawrence Berkeley National Laboratory at the US Department of Energy, in collaboration with scientists from the University of California (Berkeley) have succeeded in developing an extremely thin cloak of invisibility that can adapt itself to the shape of any three-dimensional object and mask it from detection in visible light. Although this cloaking cloak currently only exists in microscopic size, the principles underlying the technology could allow it to be extended to conceal macroscopic objects as well.
The researchers used brick-like blocks of gold nanoantennas to develop an invisibility cloak that is only 80 nanometers thick and capable of adapting itself to cover objects the size of several biological cells. The surface of the cloak of invisibility has been engineered in such a way that they can deflect the light waves that reach them, so that the object becomes invisible to optical detection in the spectral range of visible light.
"This is the first time ever that a three-dimensional object of any shape has been successfully camouflaged by visible light," said the director of the Department of Materials Science at the National Laboratory. “Our very thin cloak now looks like a coat. Simply design it and use it, and it is expandable so that you can disguise larger objects." The findings of this fascinating study were published in the prestigious journal Science.
It is the scattering of the light waves from the material - whether they are in the visible or infrared or X-rays - that allows us to locate and observe different objects. The rules that govern these interactions in natural materials can be circumvented in the framework of metamaterials where the optical properties derive precisely from their physical structure and not from their chemical composition. Over the past decade, this research team has pushed the boundaries of how light interacts with metamaterials, with researchers managing to bend the path of light or deflect it back, a phenomenon that does not occur in natural materials. Previously, optical surface cloaks, which were based on metamaterials, were bulky and could not be scaled up. In addition, the cloaks had a gap in the interface between the cloak area and the background of the environment, a flaw that made the cloak itself visible, although it still managed to mask objects that were underneath it.
"Creating a cloak that works in the air was so challenging that we had to embed it inside a dielectric prism that creates another interface of the scattered light, a mechanism that made it invisible," says one of the researchers. "At the same time, recent developments in the field of metasurfaces allow us to manipulate the progress of a light wave directly through the use of elements whose size is smaller than the size of the wavelengths of light, a mechanism that is accompanied by a dramatic confinement of light."
During the research team's experiment, a beam of red light struck a three-dimensional bone sample with an area of 1300 square microns that was wrapped in a coating consisting of gold nanoparticles. The light is scattered from the surface of the sheath in the same way as the light deflected by a flat mirror, making the objects under the sheath invisible. The cloak can be turned on and off simply by switching the polarity of the nanoparticles. "The deflection of the wave pattern achieved from each individual nanoantenna completely reproduces both the wave front and the pattern of the scattered light, so that the object remains completely masked," said one of the researchers. The ability to manipulate the interplay between light and metamaterials may provide fascinating future properties for the development of innovative technologies such as high-resolution optical microscopes and ultra-fast optical computers.
Article Summary
The news about the study
More of the topic in Hayadan:
- The cloak of the seer and the invisible is already here
- Progress towards a XNUMXD see-and-invisibility cloak
- Cloak hears "and is not heard"
8 תגובות
World critic I'm sorry but I agree with the ultra-Orthodox Jew and not with you (it's rare but sometimes it also happens) the light doesn't return to Ayyan I agree with you
Then what will be a black spot? A blue spot? How do you solve the problem of the border between the areas where the light does not return to the places where the light does return
You must take care of a continuous west so that the eye does not notice something strange ……
I think this is one step for technology and one giant step for the human race.
In the future it may be possible to find a way to expand the "cloak".
First, the claim is that the invention behaves like a mirror, which means that it is not an invisibility cloak but a cloak that is only invisible from very specific angles. In the other angles it will behave like a simple mirror.
Second, the invisibility cloak must meet the following three conditions:
1. To move forward the light coming from behind her and not deflect it. A camera and a computer need to record the light coming from behind and perform calculations to project light at the same wavelengths and angles of incidence of the original light.
2. To prevent the emission of any light from the substance that hides inside it, similar to a tiny black hole.
3. A lack of uniformity between the background and the edges of the cloak will show the outline of the bone.
It is also necessary to ask whether it is possible that the microscopic cloak described in this article really functioned properly or that it simply killed and destroyed the cells that were under it and therefore they were not seen?
A final note: in my opinion, over time the invisibility cloak will need many washes to remove impurities that will accumulate on it and interfere with the light deflection effect - can it be washed in a regular washing machine? ?
Yossi and my Lord the Jew, the article says exactly how the disappearance is done: "The surface of the cloak of disappearance was engineered in such a way that they could deflect the light waves that reach them, so that the object becomes invisible for optical detection in the spectral range of visible light."
As we know, human vision is achieved through light striking the bone being seen and returning the rays to the eyes.
If the light does not return to our eyes, we will not see!
It's not complicated.
Look outside at night in a direction from which no light reaches you and "see" that you will not see anything.
The darkness of the night is not the painting of everything black by God, but the brain's completion to a state where you simply see nothing!
An object becomes transparent if it projects to the outside an image of what is under it, or it reflects the light as if it continued through it to where it is (not necessarily to the object underneath it), so that it does not look suspicious like a tank, for example it is created by some computer controller of the cloak the background image outside the frame the bone and continues to display it exactly the same into the cloak on the cloak like a TV screen. True: the article does not really explain how the disappearance occurs.
Maybe the method here is different. I described a method of displaying on a screen which is the cloak. I do not guarantee that this is the method in the article.
But the important news is brought to our attention. In no case, in my opinion, the cloak is not transparent and does not make what is covered transparent.
Nevertheless, it seems to me in modesty that this is an important step to complete the mission of the cloak of invisibility.
It seems that there is still a long way to a shelf product. Increasing the area from a length dimension of 0.13 mm to several meters will cause considerable problems, such as synchronizing all the radiation so that it comes out with exactly the same light frequencies and with a uniform wave front. Similar to the problem of how to enlarge a television screen or how to make a uniform image from a matrix of screens, or to create a powerful laser beam from an array of Laser diodes itself is a given. Also, what happens when you fold the fabric, does the return adjust to the fold?
Okay, we understood that it bends the light rays, but how does it become transparent???
There are several degrees of seeing and not being seen
The best grade is that it is also transparent
There can be a seer and it doesn't seem to blend into the background and it's hard to see him... but he's not transparent