2020-07-03

Heavy! For the first time, the optical flow of the branch is observed, and the light can also branch infinitely from the trunk like a tree

By ddzyx

For the first time, scientists from the Israeli Institute of Technology observed branching optical flow. Their research findings were published in the journal Nature, and their important findings were published on the cover of the journal Nature. The research was conducted by PhD students Anatoly (Tolik) Patsyk in collaboration with Miguel A. Bandres. Miguel A. Bandres was a postdoctoral researcher at Technion at the beginning of the project and is now an assistant professor at CREOL in the School of Optics and Photonics at the University of Central Florida.

ClIEnrrTDJdk5QvUBkj1q7z acDcwOI4 ajc bkYRRYuKbD0HCbwpJLzw - Heavy! For the first time, the optical flow of the branch is observed, and the light can also branch infinitely from the trunk like a tree

This research was conducted by Professor Uri Sivan, President of the Polytechnic Institute and the School of Physics and Electrical Engineering, Polytechnic Institute of Solid State, and Russell Berrie Leading Professor Mordechai (Moti) Segev, Distinguished Professor of Nanotechnology Institute. When light waves propagate in landscapes that contain interference, they will naturally disperse, usually in all directions. Light scattering is a natural phenomenon that exists in many places in nature. For example, light scattering is the reason why the sky is blue. It turns out that when the length of the disturbance change is much larger than the wavelength of the light, the light wave is scattered in an unusual way:

It forms channels (branches) with increased intensity. As the waves propagate, these channels (branches) continue to split into more branches. This phenomenon is called branch flow and was first observed with electrons in 2001 and is considered Everywhere, all waves in nature will occur, such as sound waves and even ocean waves. Now, Technion researchers are introducing branch flow into the optical field:an experimental observation of branch flow. Assistant Professor Miguel Bandres said:We have always had the intention to find something new, and we are eager to find it, and finally found this thing.

Branch-like optical flow like branches

Everyone is familiar with the fact that waves propagate in homogeneous media, but for other types of media The way waves behave may be very different. When there is a disordered medium, the change is smooth, just like the scenery of mountains and valleys, waves will propagate in a special way. They will form channels that continue to split as the waves propagate, forming a beautiful pattern similar to tree branches. In the study, the research team coupled the laser beam to the soap film, which contained randomly varying film thickness.

The study found that when light travels in the soap film, the light will not be scattered, but will form a slender Branching, which causes branching light flow. In the field of optics, efforts are usually made to keep the light in focus and propagate in the form of a collimated beam, but in this study, it is surprising that the random structure of the soap film naturally caused this phenomenon of branching light flow, which is Another surprise to us from nature was only discovered now. The ability to generate branch flows in the field of optics provides exciting new opportunities for studying and understanding this general wave phenomenon.

Professor Yuri Sivin, Chairman of the Israeli Institute of Technology and Academic Chairman of the Department of Physics of Bertordo Badler, said:Nothing compares It’s more exciting to discover something new. This is the first time that light waves have proven this. This shows that interesting phenomena can also be observed in simple systems, and people only need to have enough insight to discover them. Therefore, bringing together and combining the perspectives of researchers from different backgrounds and disciplines brings some really interesting insights. Then the fact that it is observed with light waves opens up extraordinary new possibilities for research.

There is also a”branch flow” phenomenon in the light wave

First of all, it can describe the characteristics of the medium in which light propagates very accurately, You can also accurately track these branches and study their properties. Famous professor Morty Segev, Robert J. Hillman Distinguished Professor of Physics and Electrical Engineering said:Looking to the future, I always educate the research team to think beyond the horizon, to think about something new, and to watch experiments The original appearance of the facts, rather than trying to adjust the experiment to meet certain expected behaviors. In this study, Tolick tried to measure something completely different, and he was surprised to see these”light branches” that he could not explain at first.

Therefore, Miguel was invited to join the experiment, and the experiment was greatly upgraded to be able to separate the involved It took more than a year for the level of physics to finally understand that this is a strange”branch flow” phenomenon. At the time, this phenomenon was never considered in the context of light waves. Now, with this observation, many new ideas can come up. For example, use these light branches to control the fluid flow in the liquid, or combine soap with fluorescent materials to make the branches a small laser. Or use a soap film as a basic platform for exploring waves, such as the transition from ordinary scattering, which is usually diffuse, to branch flow.