Photonic Origami for On-chip 3D Micro-Optics

We fold micrometer-thick silica sheets into three-dimensional photonic devices on a silicon chip using a laser-induced local melting. Our structure contains parabolic micromirrors and microresonators with Q-factors exceeding 8 × 10⁶, which can be folded with milliradian resolution into knees and helices. This method extends silica photonics into the third dimension, providing a scalable, chip-compatible route to micro-optics for data processing, sensing, and precision tests of fundamental physics such as deviations from Newtonian gravity.