Ultra-broadband parallel chaos generation in photonic crystal fibers with ultrafast laser pumping

Laser chaos, a physical system capable of hosting chaotic phenomena, exhibits the characteristic irregular appearance and high sensitivity to initial conditions, both hallmarks of nonlinear dynamical systems, and has found widespread application in chaotic optical communications. Here, a scheme for generating ultra-broadband optical chaos is proposed and experimentally validated. This scheme utilizes a 1064 nm ultrafast pulsed laser to pump a photonic crystal fiber, enabling the simultaneous generation of chaotic signals with a wideband spectrum and high complexity across multiple distinct wavelength bands. The wavelength range of the generated multi-channel complex chaotic signals spans from the visible to the near-infrared range (480-1900 nm). Furthermore, each channel can be independently selected, and its spectral width is tunable, allowing for adaptation to various application requirements. Specifically, the effective bandwidth of each multi-channel chaotic signal reaches approximately 20 GHz. Notably, the cross-correlation coefficients between different channels simultaneously generated are faint. In contrast, the presence of extreme correlation peaks within the cross-correlation can effectively eliminate crosstalk between different chaotic optical channels. This proposed scheme offers a promising solution for parallel chaos generation, showcasing significant potential applications in fields such as optical frequency combs, multi-channel chaotic communication, multi-random bit generation, and parallel light detection and ranging.