Research on ultracold cesium molecule long-range states by high-resolution photoassociative spectroscopy

• Published in: Science China. Physics, mechanics & astronomy Vol. 51; no. 2; pp. 147 - 156
• Main Authors: Wang, LiRong, Ma, Jie, Ji, WeiBang, Wang, GuiPing, Xiao, LianTuan, Jia, SuoTang
• Format: Journal Article
• Language: English
• Published: Beijing Science in China Press 01.02.2008; Springer Nature B.V
• Subjects: Astronomy; Cesium; Classical and Continuum Physics; High resolution; Observations and Techniques; Optical traps; Physics; Physics and Astronomy; Signal to noise ratio; Spectroscopy; ultracold molecule; photoassociation; high-resolution spectrum
• ISSN: 1672-1799; 1674-7348; 1862-2844; 1869-1927
• DOI: 10.1007/s11433-008-0024-7

In this paper, an ultra-high resolution photoassociation spectroscopy study on photoassociation of cesium atoms is reported. The cold cesium gas in the magneto-optical trap is illuminated by a photoassociation laser with red-tuning as large as 40 cm −1 below the 6 S 1/2 + 6 P 3/2 dissociation limit, and the photoassociation to the excited state ultracold molecule is detected. High signal-to-noise ratio is obtained by using the lock-in detection of the fluorescence from the modulated cold Cs atoms. The 0 g − , 1 g and 0 u + long-range states which correspond to 6 S 1/2 + 6 P 3/2 dissociation limit are present in the photoassociation spectrum. The effective coefficients of leading long-range interactions and the corresponding vibrational quantum number are obtained using LeRoy-Bernstein Law. It is found that photoassociation process creates rotating molecules and the high J value is a hint that higher partial waves participate in the PA process in the presence of trapping laser.