Ultrastable laser referenced on velocity-grating atom interferometry

Abstract

A laser with superb frequency stability plays an important role in fundamental physics research and advanced technologies. Frequency references are usually utilized to stabilize the laser, such as high-finesse cavities and atomic ensembles, of which thermal atomic beams are attractive because of their balanced performance between simplicity and stability. However, due to the transverse-velocity distribution in the thermal atomic beams, most atoms (generally $>99%$) are wasted when interacting with the laser. Here, we propose a laser referenced on a version of velocity-grating Ramsey-Bord\'e atom interferometry with greatly improved atom utilization and thus superior laser frequency stability. Compared with a conventional atomic interferometry applied to stabilize the laser, the proposed system in principle generates optical Ramsey fringes with the amplitude enhanced by 1000-fold or more. Such a configuration has promising applications in diverse areas, including precision measurements and quantum metrology.