Harvard Scientists Discover Unexpected New States of Light

Image Credit: Capasso Lab/Harvard SEAS

 Researchers at Harvard University have developed a material that can generate and maintain newly discovered complex states of light. This tool utilizes polarization to generate unseen structures such as swirling vortices, spirals and corkscrewn that help scientists better understand light's properties and its potential practical applications.
 The new tool - a type of metasurface - takes advantage of something called angular momentum along with a second type, known as spin angular momentum (or also known as circular polarization).
 "Think about orbital angular momentum and circular polarization like the motion of a planet," wrote Harvard's Leah Burrows in a statement. "Circular polarization is the direction in which a planet rotates on its axis while orbital momentum describes how the planet orbits the sun."
 Using this new tool, scientists have circumvented past restrictions which allowed only certain polarizations of light to connect with certain angular momentums. This material allows any polarization to be converted to any orbital angular momentum, creating forms of light that could be useful in high-speed data transfer and encoded communications.
 It has only been 25 years since light was discovered to have orbital angular momentum. In this time, significant milestone have been made into the research of light, such as the first-ever photograph of light behaving as both a particle and a wave back in 2015.

Read the official press release at: https://www.seas.harvard.edu/news/2017/11/strange-new-world-of-light
Or read the full study at: http://science.sciencemag.org/content/early/2017/11/01/science.aao5392