High-quality microwave signals generated from tiny photonic chip
A high-level schematic of the photonic integrated chip, developed by the Gaeta lab, for all-optical optical frequency division, or OFD—a method of converting a high-frequency signal to a lower frequency. Credit: Yun Zhao/Columbia Engineering In a new Nature study, Columbia Engineering researchers have built a photonic chip that is able to produce high-quality, ultra-low-noise microwave