Programming Light on an Ultra-Small Scale.

• Position: NANOPHOTONICS

A unique platform to program a layered crystal, producing imaging capabilities beyond common limits on demand, has been developed by a team of researchers led by Columbia University. The discovery is an important step toward control of nanolight, which is light that can access the smallest length scales imaginable. The work also provides insights for the field of optical quantum information processing, which aims to solve difficult problems in computing and communications.

"We were able to use ultrafast nano-scale microscopy to discover a new way to control our crystals with light, turning elusive photonic properties on and off at will," says postdoctoral researcher and lead investigator Aaron Sternbach. "The effects are short-lived, only lasting for trillionths of one second, yet we are now able to observe these phenomena clearly."

Nature sets a limit on how tightly light can be focused. Even in microscopes, two different objects that are closer than this limit would appear to be one, but within a special class of layered crystalline materials--known as van de Waals crystals--these rules can, sometimes, be broken. In these special cases, light can be confined without any limit in these materials, making it...