Spatiotemporal dynamics of a passively mode-locked Nd:GdVO(4) laser.

By examining beam patterns, temporal pulse forms, and radio-frequency spectra as functions of resonator configuration and pump power, we found that a passively mode-locked Nd:GdVO4 laser exhibited four main regimes of operation that were single-transverse-mode Q-switched mode locking (QSML), single-transverse-mode continuous-wave mode locking (CWML), multiple-transverse-modes QSML, and multiple-transverse-modes CWML. The effect of multiple transverse modes on CWML was giving rise to amplitude instability in the pulse train. In the regime of multiple-transverse-modes QSML, we observed the phenomenon of spatiotemporal dynamics that spatial patterns vary with the time.