Exploiting the etalon effect to manipulate the pulse characteristics of a self-mode-locked Nd:YVO4 laser with a flexible cavity length

Three longitudinal mode oscillation states and their corresponding pulse characteristics were obtained by exploiting the etalon effect in a self-mode-locked (SML) laser. Various longitudinal mode oscillation states and corresponding optical spectra were first theoretically analyzed by employing different simulation parameters. In the experiments, by increasing the ratio of the etalon thickness to the laser cavity length and tuning the laser crystal heat sink temperature, the SML laser successively experienced the adjacent longitudinal mode, multigroup longitudinal mode, and spaced longitudinal mode oscillation states. The experimental results showed that when the laser cavity length increased from 55 to 95 mm and the etalon thickness increased from 4 to 41 mm, the output power decreased from 801.32 to 603.63 mW at a pump power of 6.51 W. The number of locked modes in the SML laser increased from six to nine initially, and it then decreased to four, corresponding to the SML pulse repetition frequency increasing from 2.70 to 4.00 GHz and then decreasing to 1.58 GHz. The experimental results were in good agreement with the theoretical analysis.

Automated summary

Three longitudinal mode oscillation states and their corresponding pulse characteristics were obtained by utilizing the etalon effect in a self-mode-locked laser. The experimental results showed good agreement with the theoretical analysis.