(The) passive mode-locking of ruby laser

Abstract

The mode-locked pulses train with DDI in methanol as a saturable absorber is observed. To obtain $\mbox{TEM_{OO}}$ transverse mode, the mode selector with an aperture of 2mm diameter is used. The single pulse whose pulse-width is estimated as 200ps by two photon fluorescence(TPF) photography is selected from the pulse train by sparkgap-triggered optical gate. In conventional mode operation, it is observed that the laser spiking has the irregular amplitude, duration and separation.