We all learned in science classes that light rays move in straight paths and are scattered by a process known as "diffraction" - and that they cannot go around corners. But now, scientists from Tel Aviv University are testing new applications of their recent discovery that small light rays can indeed be bent in a laboratory environment and that they bypass much less than "normal" rays Nature Photonics
These rays, called "Airy beams", were named in honor of the English astronomer Sir George Biddell Airy, who studied the curved paths of light in rainbows, and which were first produced at the University of Florida. Now, Professor Adi Arie and his students Tal Allenbogen, Noa Wallach-Bloch, Ayelet Ganni Pedovitz and Ido Dolev from the Faculty of Engineering at Tel Aviv University have demonstrated new ways to produce and control rays of this type. Their research, which used an innovative algorithm and special non-linear optical crystals, was published in the scientific journal Nature photonics.
Some of these new applications, such as a light source for creating beams capable of going around corners, or illuminated enclosures that do not contain visible light sources, are still fifteen years away, says Professor Aryeh. However, this research also has immediate applications. For example, since tiny particles are "attracted" to the highest intensities of the beam, the pharmaceutical and chemical industries can use the new beam to sort particles according to their size or quality and to filter out contaminants from medicines, which would otherwise lead to poisoning and even death.
Until now, according to another article that was also published in the scientific journal Nature photonics, Airy rays were created through "linear diffraction" using means that radiate monochromatic light through glass panels of varying thickness. However, using crystals they developed in their laboratory, the approach of the researchers from Tel Aviv University utilizes another method: non-linear optics. Following their projection towards the crystals, the light waves "bounce" inside the crystal, changing their wavelength and color. Through this method, the researchers point out, a window will be opened for the development of new light beams with new wavelengths with greater control over their paths.
"We found a way to control the iris beam to be directed to the right or left, as we wish, for example," explains the lead researcher. In addition, the researchers also found a way to control the position of the peak intensity of the rays, which are created through a process of non-linear optics.
Non-linear optics (Wikipedia entry, Nonlinear optics) is a subfield of optics that discusses the response of materials to high intensities of radiation. The strong interactions between radiation and matter result in the creation of new colors, which have half the wavelength of the original light frequency that was absorbed. For example, a non-linear response to infrared light is capable of producing visible light - as seen in those bright green laser pointers used in presentations given in large rooms.
Airy rays hold the potential for significant progress for engineers. They could be used as a basis for the technology behind the "light bullets" of the space age - as efficient and accurate technologies for the police and the army, but also as an innovative communication interface between transmitters and receivers. As tiny, compressed packets of information, these aerial rays will be able to move in the open air - the researchers hope.
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In light of the comments, a new version of the article was uploaded.
Thanks to all the responders.
sympathetic,
True, this is not a soliton solution
This is a plasma shock wave solution.
to Professor Aryeh
Thanks for correcting the mistakes in the translation of the article. A mistranslation can severely impair understanding.
Thanks to Michael for referring Professor Aryeh to explain the article
There are still several unclear points in the article and I tend to attribute them to the translation. what does it mean
"Little rays of light"? appearing in the article.
If I understood correctly, it is of course possible to deflect light rays with the help of crystals, prisms, lattices
As Tzvi pointed out, but the idea here is that the intensity of the beam combined with the non-linear range
Allows to deflect the beam?
By the way Zvi I think but I'm not sure that Airey beams are indeed solitons but
It was impossible to understand this explicitly from the reaction of Adi Aryeh, he simply stated that they
are eigenfunctions of the Helmholtz equation.
http://en.wikipedia.org/wiki/Airy_beam
The term non-linear optics used by the reporter is not accurate and should have been non-linear optics. Even instead of the term refraction, it is customary to use the term diffraction. As for Airy beams, these are beams whose central lobe performs a parabolic path in space, and therefore these beams are also called accelerating beams. In this they differ from the more familiar beams such as Gaussian beams emitted by lasers, whose central lobe progresses in a straight line. Despite their acceleration properties, Airy beams do not contradict any of the known laws of optics and constitute an analytical solution to the equation of the progression of waves in free space, called the Helmholtz equation.
More details can be found in the following article:
Tal Ellenbogen et al, Nonlinear generation and manipulation of Airy beams. Nature Photonics, 2009; 3 395 DOI: 10.1038/nphoton.2009.95
Zvi and Ehud:
It seems to me that Moshe Nachmani's translation is faithful (with the exception of the unsuccessful choice of the term "non-linear" as a translation of "non-linear") to the source published in Sainsdaily, which also deals with movement in non-straight lines in a normal medium.
I sent an email to Professor Adi Aryeh and asked for his opinion.
Ehud's comment on this article is super important and requires the writer's attention as it illuminates the entire article in a different light!
The light rays move in a uniform medium in straight lines and if they changed it then it is very interesting, very strange and probably not true.
What's more, it is possible to cause light to be refracted by: crystals, lattices, prisms, etc., and this may have been done here for technical reasons - so that they could look at the intensities of light at different ends of the spectrum.
The term non-linearity is not at all related to the question of movement in straight or curved lines - it is an expression that refers to the classification of the physical equation that describes the system. There are non-linear effects in optics that originate from higher orders of approximately linear equations (this is why we don't see non-linear optical effects in everyday life). I don't want to get into mathematical subtleties, but it is clear that this is about non-linear optics, since it is about changing the color of the rays and it is an effect that originates from non-linear optics.
Finally, the Airy function mentioned is, I'm not mistaken (I'll check it by tonight) a soliton solution of waves in the plasma - that is, a solution that does not change during the movement. If this is indeed the case, this is an explanation for the fact that this function will be a "bullet of light", since it will not "spread" during its movement but will maintain its shape.
Could this method create a black hole that would swallow the Earth?
There is no such thing as nonlinear optics. The term is nonlinear optics and the difference is no
Semantic only!!!
Non-linear optics does not deal with optics in which the rays do not move in lines
straight but in materials with optical properties that change according to the passing light
Through them! The translation error has the potential to completely confuse readers.
The discovery here in my opinion is not physical but simply engineering instead of a beam
Gaussian, a beam is produced whose profile is determined by a function known as
Airy function. The ability to deflect the horn to the right or left is a combination of
The profile of the light beam with the non-linear properties of the crystals.
It's a combination.. In Tel Aviv there is cooperation. Nevertheless, engineers build and physicists research in the basic way..
It says that this achievement was achieved by researchers from the Faculty of Engineering. I'm interested to know why not physicists? I thought that the field of optics and crystals belonged to the research fields of the Faculty of Physics.
I wonder if this method (if you consider it) will be able to predict more accurate results of gravity drainage?
Or with the help of the method it will be possible to build more sophisticated screens?