"Topology guide of light", the article by Alberto Amo Garcia in La Recherche

"Deemed to be more economical and faster, chips using light instead of electricity - photonic chips - could equip the computers of the future. However, photons are more difficult to manipulate than electrons. A promising strategy consists in resorting to properties of a discipline called "topology", which studies shapes in order to design circuits structured with a certain symmetry; this would improve the efficiency of photon transport, especially in bends, as light travels in a privileged way in a straight line. "