Fig. 1. Schematic diagram of the arm locking structure

Fig. 2. Arm locking circuit structure

Fig. 3. Step response of the Padé approximation for different orders of the delay segment

Fig. 4. The variation of the arm lengths

Fig. 5. Schematic of bilayer optimization strategy

Fig. 6. Boxplots of evaluation indicator for different pairs of zero poles

Fig. 7. Close-loop transfer function bode plot

Fig. 8. Structure of single arm locking simulation

Fig. 9. Time domain noise signal

Fig. 10. Technical noise amplification in frequency domain

Fig. 11. Laser frequency noise suppression in frequency domain

Fig. 12. Single arm locking system simulation results

Fig. 13. All noise frequency domain analysis