Laser with feedback: an optical implementation of competing instabilities, Shil’nikov chaos, and transient fluctuation enhancement

Abstract

A CO2 laser with feedback shows different dynamic regimes depending on the dominant role of one or two of three coexisting unstable stationary points. These regimes have been characterized by statistical distributions of return times to a Poincare section at constant intensity. In particular, in the regime of Shil’nikov chaos the iteration maps of return times display a statistical spread owing to a transient fluctuation enhancement phenomenon peculiar to macroscopic systems, which is absent in low-dimensional chaotic dynamics.