Monolithically integrated stretchable photonics

A stretchable material for creating optical components could form the basis of wearable health monitors. Flexible electronics and photonics offer a way of integrating devices into clothing or attaching components directly to the skin. But many applications require optical materials that are both bendable and stretchable. Juejun Hu from the Massachusetts Institute of Technology, USA, and co-workers have incorporated a chalcogenide glass and an epoxy polymer into an elastomer substrate. This choice of materials permits the seamlessly integration of photonic components with both high and low index contrasts in the same platform. While the glass and epoxy are intrinsically brittle, the composite material is stretchy because the optical components are located in ‘islands’ and interconnected by optical waveguides with a serpentine shape. The material exhibited no measurable degradation in optical performance after 3000 stretching cycles.