Colored-noise-induced first-order phase transition in a single-mode dye laser

We report the observation of a colored-noise-induced first-order nonequilibrium phase transition in a single-mode dye laser. Although a second-order phase transition exists in the more usual single-mode laser models, the order of the phase transition can be altered by including colored-noise fluctuations in the pumping of the laser. The nonwhite character of the noise is shown to be crucial to the onset of the characteristics of a first-order phase transition.