Phys.org  September 13, 2019
An international team of researchers (USA – University of Pennsylvania, Italy) has developed a prototype photonic chip that is roughly 250 microns square and features a tessellated grid of oval rings. By pumping the chip with an external laser, targeted to alter the photonic properties of individual rings, they are able to alter which of those rings constitute the boundaries of a waveguide. The result is a reconfigurable topological insulator. By changing the pumping patterns, photons headed in different directions can be routed around each other, allowing photons from multiple data packets to travel through the chip simultaneously. They were able define the edges such that photons can go from any input port to any output port, or even to multiple outputs at once which means the ports-to-footprint ratio is at least two orders of magnitude greater than current state-of-the-art photonic routers and switches. The system is robust against unexpected defects. The system is not yet small enough to be useful for data centers or other commercial applications. Next steps for the team will be to establish a fast reconfiguring scheme in an integrated fashion…read more. TECHNICAL ARTICLEÂ
By pumping individual rings with an external laser, they are able dynamically redefine the path photons take. Credit: University of Pennsylvania