New metasurface can tune laser light without additional components

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What They Say

A team of researchers at Harvard have developed a metasurface that can tune the amplitude, phase, and polarization properties of laser light, including the wavelength. No additional components are needed. The research was published in Nature Communications. Up to now, these changes could be made by using separate metasurfaces, but this was inefficient. The new approach uses the idea of adjacent cells which form a ‘supercell’ to process the light.

The metasurface can split light into multiple beams and control their shape and intensity in an independent, precise and power-efficient way.

Christina Spägele, a graduate student at SEAS and first author of the paper told ElectroOptics.com

“When light hits the metasurface, different colors are deflected in different directions. We managed to harness this effect and design it so that only the wavelength that we selected has the correct direction to enter back in the diode, enabling the laser to operate only at that specific wavelength.”

To change the wavelength, the researchers simply move the metasurface with respect to the laser diode.

What We Think

It really is amazing what is being done in R&D Labs! (BR)

MultifunctionMetasurfaceThe incident light can be split into three independent beams, each with different properties — a conventional beam (right), a beam known as a Bessel beam (center) and an optical vortex (left). (Credit: Christina Spägele/Harvard SEAS)