Photonic chip for laser stabilization to an atomic vapor with 10-11 instability

Devices based on spectroscopy of atomic vapors can measure physical quantities such as magnetic fields, RF electric fields, time and length, and rotation and have applications in a broad range of fields including communications, medicine, and navigation. We present a type of photonic device that interfaces single-mode silicon nitride optical waveguides with warm atomic vapors, enabling precision spectroscopy in an extremely compact (<1 cm(3)) package. We perform precision spectroscopy of rubidium confined in a micro-machined, 27 mm(3) volume, vapor cell using a collimated free-space 120 mu m diameter laser beam derived directly from a single-mode silicon nitride waveguide. With this optical-fiber integrated photonic spectrometer, we demonstrate an optical frequency reference at 780 nm with a stability of 10(-11) from 1 to 10(4) s. This device harnesses the benefits of both photonic integration and precision spectroscopy for the next generation of quantum sensors and devices based on atomic vapors. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement