Scientists at the University of Salamanca, in collaboration with the Argonne National Laboratory (ANL) have developed a research can be an important step to control matter through light at an extremely small scale.
The Research Group Applications laser and Photonics (ALF-USAL) is a specialist in the generation of coherent radiation in the ultraviolet and X – ray radiation can observe or interact with matter at the nanometer scale in a millionth of a millimeter.
Now, an article just published by the journalPhysical Review Letters , reveal new strategies for generating this radiation in the form of vortices of light, light beams rotating and could be used to manipulate matter at this small scale. The process for generating radiation in the ultraviolet and X – rays, the LFA-group USALbeen studied for years, it is known as harmonic generation of high order. This is a fairly complex process. It is highly nonlinear, nonperturbative and which results in very coherent radiation, ie, very orderly radiation
Since 2013, the ALF-USAL group has become an international benchmark in the research on the possibility of generating this high frequency radiation in the form of vortices of light.
“a vortex is like a swirl of light and is very interesting because it can transmit this rotation to matter , ” says Laura Rego, research group and first author of the article. Its uses are varied: from communications, as a way of encoding information to be transmitted to a tool for rotating particles, to quantum computing.
Today, and vortices occur in the range of visible light and they are exploring all these applications. The ALF-USAL group has identified a way to generate these vortices of light with high frequency radiation (ultraviolet and X -rays), allowing, for now, transmit rotation bearing the vortices very small objects at nanometric scales. “The shorter the wavelength of light our increasingly arrive at a smaller scale , ” explains the researcher.
Various speeds
To advance along this path, the study just published makes a major contribution. “Until now had seen these vortices produced ultraviolet light with a single speed of rotation , ” says Carlos Hernandez Garcia, a member of the team. In fact, for each wavelength, or color of light, it was established that there was only a rotational speed as possible.
However, “we have now found that in normal situations also can generate vortices of one color with much wider range of speeds. “This means you could select and control the speed with rotating vortices ultraviolet light, multiplying the possibilities that could offer this technology in the future.
“It is a new control key on the interaction of light with matter: now can induce rotations of different speeds within the same wavelength “said Julio San Roman.
it is known that there are other methods to generate vortices X – ray, but they offer a very low quality as first generate the X – rays and then try to produce vortices rotating them by techniques today are very inefficient.However, by generating harmonics is achieved in a direct and more efficiently.
The University of Salamanca carried out this research at the theoretical level, so that means “a guiding light subsequent experiments.” Therefore, possible technological applications would be still far away. However, “so far are the only ones who have made a theoretical simulation of this type are exploring new scenarios and maybe we can work with any experimental group , ” says Luis Plaja. In fact, in this new work also he involved the researcher Antonio Picon, the Argonne National Laboratory in the United States.
