High-performance frequency stabilization of ultraviolet diode lasers by using dichroic atomic vapor spectroscopy and transfer cavity**Project supported by the National Natural Science Foundation of China (Grant Nos. 11704408 and 91836106), the Beijing Natural Science Foundation, China (Grant No. Z180013), and the Joint Fund of the Ministry of Education, China (Grant No. 6141A020333xx).

Abstract

We develop a high-performance ultraviolet (UV) frequency stabilization technique implemented directly on UV diode lasers by combining the dichroic atomic vapor laser lock and the resonant transfer cavity lock. As an example, we demonstrate a stable locking with measured frequency standard deviations of approximately 200 kHz and 300 kHz for 399 nm and 370 nm diode lasers in 20 min. We achieve a long-term frequency drift of no more than 1 MHz for the target 370 nm laser within an hour, which is further verified with fluorescence count rates of a single trapped 171Yb+ ion. We also find strong linear correlations between lock points and environmental factors such as temperature and atmospheric pressure. Our approach provides a simple and stable solution at a relatively low cost, and features flexible control, high feedback bandwidth and minimal power consumption of the target UV laser.