Laser frequency locking based on the normal and abnormal saturated absorption spectroscopy of 87Rb
Wan Jian-Hong, Liu Chang, Wang Yan-Hui†,
       

Modification of the probe laser intensity in the transition 52S1/2, F = 2–52P3/2, F′ = 3 of the 87Rb. The I, I0, t denote the modifications of the probe laser intensity, probe laser intensity, and time.