Fig. 1. Experimental setup and schematic. (a) Experimental setup for molasses- and sideband-cooling; (b) energy-level schematic of ⁸⁷Sr atom; (c) timing sequence of molasses- and sideband-cooling

Fig. 2. Longitudinal resolved sideband spectra and radial spectra at 182E_r under different cooling schemes. (a) Longitudinal resolved sideband spectra, and solid lines represent Lorentzian fitting results; (b) radial spectra with and without cooling, and solid lines represent Gaussian fitting results

Fig. 3. Rabi oscillations as functions of interrogation time under different cooling schemes, and solid lines represent fitting results under the corresponding parameters^[16]

Fig. 4. Remaining atom fraction after adiabatically ramping to indicated trap depth from 218E_r after molasses- and sideband-cooling and without cooling