Enhancement of the 123.6 nm light intensity in a krypton lamp by optical pumping

• Published in: Optics and laser technology 2023-12, Vol.167, p.109725, Article 109725
• Main Authors: Liang, Jianwei, Feng, Gaoping, Du, Baosheng, Rao, Wei, Song, Junling, Zhu, Xiaoxiao, Han, Jianhui, Zheng, Yongzan, Wang, Mingdong, Hong, Yanji
• Format: Article
• Language: English
• ISSN: 0030-3992; 1879-2545
• DOI: 10.1016/j.optlastec.2023.109725

•An increase on the 123.6 nm light intensity by optical pumping was demonstrated in a krypton lamp.•The enhancement occurs mainly in the discharge area.•The light intensity in flowing gas mode was markedly higher than that in static gas mode. In this work, we report a method to significantly increase the intensity of vacuum ultraviolet (VUV) light at 123.6 nm in a krypton lamp. Additional VUV photons were obtained by quenching metastable atoms via optically pumping the 4p5 (2P°3/2)5s 2[3/2]°J=2–4p5 (2P°3/2)5p 2[5/2]J=2 transition at 810.7 nm. Compared with static gas conditions, the spectral data indicated a remarkable intensity enhancement of 123.6 nm VUV light by flowing gas without optical pumping. Under the 810.7 nm optical pumping, the VUV light intensity at 123.6 nm increases with the increase of laser powers and beam diameters, which mainly takes place in the discharge area. Mostnotably, a 37% enhancement on 123.6 nm VUV light intensity was achieved with a longitudinal 9 mm beam diameter, 906 mW of 810.7 nm laser pumping at flowing gas mode, which is of great significance for all-optical atom trap trace analysis.