A vibration modulation method for natural mode measurement of external-cavity diode laser

A vibration modulation method is introduced for natural mode measurement of external-cavity diode laser. The detuning power spectrum of the Fabry-Perot resonator is investigated by actively driving frequency range (0 ∼3 kHz) acoustic field to provide a vary series of sound waves loading on the laser structure, from which the natural modes of external-cavity diode laser are reflected intuitively. Furthermore, the impact of external noise using the acoustic pressure model is analyzed. The experimental results are in good agreement with the theoretical analysis results. The proposed method can optimize the laser mechanics structure in stability and design feedback system in natural frequency respect in order to achieve better frequency stabilization effect.