Fig. 5: Optical frequency and timing diagram for the PIC-compatible laser system.

a Optical transitions of ⁸⁷Rb atoms (D2 transition)⁷⁹ for LPAI operation. Cooling, Detection, Depump, and Raman 1 beams use \(\left|F=2\right\rangle \) to \(\left|F^{\prime} =1,2,3\right\rangle \) transitions (Left peaks), and Repump and Raman 2 beams use \(\left|F=1\right\rangle \) to \(\left|F^{\prime} =0,1,2\right\rangle \) transitions (Right peaks). The 1560 nm seed laser is frequency-doubled to 780 nm and locked to \(\left|F=2\right\rangle \) to \(\left|F^{\prime} =2,3\right\rangle \) crossover transition with ~1.15 GHz red-detuning from the \(\left|F=2\right\rangle \to \left|F^{\prime} =3\right\rangle \) resonance, which is also used for Raman 1. b Diagram of the timing sequence for LPAI operation highlighting important dynamic changes in the laser channels. The pulse width of Repump/Detection/Raman is not to scale.