Two extended-cavity diode lasers at 780 nm which are longtime frequency-stabilized to Rb^（87） saturated absorption signals are reported.A high-performance frequency-locking circuit module using a first-harmonic detection technique is designed and achieved.Two lasers are continuously frequency-stabilized for over 100 h in conventional laboratory condition.The Allan standard deviation of either laser is estimated to be 1.3×10^（-11） at an integration time of 25 s.The system environment temperature drift is demonstrated to be the main factor affecting long-term stability of the stabilized lasers based on our correlation study between beat frequency and system environment temperature.
A laser power feedback control system that features fast response, large-scale performance, low noise, and excellent stability is presented. Some essential points used for optimization are described. Primary optical lattice experiments are given as examples to show the performance of this system. With these performance characteristics, the power control system is useful for applications in cold atom physics and precision measurements.
