U.S. scientists say they’ve encoded an entire image’s worth of data into a single photon, stored it and then retrieved the image intact. University of Rochester researchers say the ability to squeeze that much information into so small a space and retrieve it intact opens the door to optical buffering — the ability to store information as light. “You can have a tremendous amount of information in a pulse of light, but normally if you try to buffer it, you can lose much of that information,” said Ryan Camacho, Howell’s graduate student and lead author on the article. “We’re showing it’s possible to pull out an enormous amount of information with an extremely high signal-to-noise ratio even with very low light levels.”

By using a single photon, the team played on a strange property of light: quantum mechanical theory holds that while light is emitted as discrete particles called photons, it can also be thought of as a wave. As a wave, the light passed through all parts of the stencil at once, carrying the ’shadow’ of the UR with it. The photon then entered a 10 cm long tube filled with cesium gas heated to 100