A new way to slow the rate at which light moves has been developed by scientists which they believe that one day could pave way to the development of new sensor technology.
It has been long known scientifically that a wave packet of light travels slower through matter. The degree of this gradual decrease in the speed of light when it passes materials like water or glass is less than a factor with other research groups using complex manipulations of the properties of crystal lattices or atomic vapors to promote increase in number.
In the new technique, an international group of scientists have chosen to use liquid crystal matrix similar to the one found in computer display and LCD televisions. The simple setup does not require magnetic fields or external voltages, just a capability of working at a room temperature with low optical power.
Then, they placed additional chemical component that entwines the liquid crystal molecules into a helical shape in addition to dye molecules that snuggled down inside these structures. When irradiated by light, dye molecules change their shape and optical properties were altered thus resulting to a change in the relative velocities of the light pulse’s wave components as it passes through.
The researchers wrote in the report that they were able to "reduce the group velocity of light back to less than one-billionth of its top speed."
Additionally, this helical structure guarantees a prolonged lifetime for the shape-shifted dyes, permitting the probability of storing a light pulse in the medium and then giving it away later on demand.
Moving on, the researchers say that they are planning on trying their approach in comparable phase sensing applications as well as probably extending the work to other types of dye and molecular arrangements.
Umberto Bortolozzo, one of the study’s author said, "Realizing slow and stopped light in these media is very exciting both for the fundamental research that discovers such new effects in soft matter systems and for the new possibilities that these investigations could open in the fields of remote sensing and optical storage."
This study is published in the journal Optics Letters and Optics Express.
