Effects of intrinsic spontaneous-emission noise on the nonlinear dynamics of an optically injected semiconductor laser

The effects of intrinsic spontaneous-emission noise on the nonlinear dynami cs of an optically injected semiconductor laser is quantitatively studied t hrough a single-mode model. It is found that fur periodic motions, the effe ct of this noise source is to kick phase points off the underlying determin istic limit cycle. When the noise is not too strong so that phase points ca n stay near the limit cycle, phase points execute Brownian-like motions. Wh en the noise is very strong, or the convergent flow near the attractor is w eak, noise instantly kicks phase points away from the attractor to a region where nonlinearity is very strong. Then the diffusional process is slower than a standard Brownian motion. For chaotic motions, the characteristic sh ort-term predictability of chaos is destroyed with an increasing amount of noise. The chaotic motions near the periodic/chaotic boundary, as well as a t some locations inside the chaotic region, are more susceptible to noise. This suggests that there may exist fine structures inside the chaotic regio n. [S1050-2947(99)01302-5].