Negative refraction achieved with atoms instead of metamaterials

Negative refraction - a phenomenon where light bends in the opposite direction to its usual behaviour - has potential to transfom optics, enabling transformative technologies such as superlenses and cloaking devices.

Now, carefully arranged arrays of atoms have brought these possibilities a step closer, achieving negative refraction without the need for metamaterials.        

In research published in Nature Communications, Lancaster University physics Professor Janne Ruostekoski and Dr Kyle Ballantine, with Dr Lewis Ruks from NTT Basic Research Laboratories in Japan, demonstrated a novel way of controlling interactions between atoms and light.

Natural materials interact with light through atomic transitions, where electrons jump between different energy levels. According to Lancaster University, this interaction process has limitations; light primarily interacts with its electric field component, leaving the magnetic field component largely unused.

These inherent constraints in the optical properties of natural materials have driven the development of artificially engineered metamaterials which rely on the phenomenon of negative refraction.