New spin on topology: spin guided light scattering has been observed in a liquid crystal (Courtesy: Shutterstock/Serg-DAV) Just as topological insulators provide protection to electrons travelling ...

A wave impinges from the left (blue) onto a disordered medium (grey). A part of the wave transmits to the right, the rest is reflected back to the left. By adding gain (red) and loss (green) with a ...

Usually, light waves can pass through each other without any resistance. According to the laws of electrodynamics, two light beams can exist in the same place without influencing each other; they ...