Physicists set record confining laser pulse to air waveguide in 45m corridor, inspiring new applications.
Physicists from the University of Maryland have achieved a breakthrough in laser confinement, setting a new record by confining a self-focused laser pulse to a cage of air down the length of a 45 meter-long university corridor. This experiment, led by physicist Howard Milchberg, has been accepted into the journal Physical Review X, and could have implications for long-range laser-based communications or even advanced laser-based weapons technology.
The technique of laser confinement is known as a waveguide, which involves guiding electromagnetic waves down a specific path and preventing them from scattering. This is typically done with optical fibers, which consist of a glass tube with a lower refractive index around the outside, causing light to bend back into the tube and maintain the beam along its length. In 2014, Milchberg and his colleagues successfully demonstrated an air waveguide, which uses laser pulses to create a plasma that heats the air in its wake, leaving behind a path of lower-density air. This lower density air has a lower refractive index, effectively creating a waveguide out of the air.
The UMD team was able to create a waveguide capable of traversing a 45 meter corridor, retaining 20% of the light that would have been lost without a waveguide. They also studied an 8-meter waveguide in the lab, which was able to retain 60% of the light that would have been lost. The team wants to try different colors of laser light and a faster filament pulse rate to guide a continuous laser beam.
The findings of this research point to the potential for even longer waveguides and many applications. The team believes that with the right lasers, they could extend their guides to one kilometer and beyond. The research has been accepted in Physical Review X, and is available on arXiv.
This breakthrough in laser confinement has the potential to open up a range of applications, from long-range laser-based communications to advanced laser-based weapons technology. The UMD team has set a new record by confining a self-focused laser pulse to a cage of air down the length of a 45 meter-long university corridor, and have demonstrated the potential for even longer waveguides. With the right lasers, they could extend their guides to one kilometer and beyond. This research has been accepted in Physical Review X, and is available on arXiv.
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