The diode-pumped Nd:vanadate laser is one of the most widely used lasers in the near-infrared range. Using passive Q-switching with a Cr:YAG saturable absorber, it generates nanosecond pulses at tens of kilohertz. It is well known to display either regular pulsing or low-dimensional deterministic chaos, depending on the absorber's position within the cavity. However, to our knowledge, a strange nonchaotic attractor (SNA) has never been reported in this system. Our experiments provide evidence that, for a specific absorber position, the laser dynamics correspond to a strange nonchaotic attractor. SNAs exhibit complex dynamical behavior that is neither periodic nor chaotic, positioning them as a valuable resource for applications requiring high spectral diversity while preserving predictable dynamics. By experimentally obtaining time series of two laser variables, we reconstruct the underlying attractor. For a certain position of the SA, we find that all Lyapunov exponents are negative and that the energy spectra exhibit a broad frequency range, indicating that the attractor is nonchaotic and lacks periodicity. Using Higuchi's method, we estimate the fractal dimension $\left(d_f\right)$ and find that $13\%$ of the nonchaotic time series exhibit a well-defined $d_f$, confirming the presence of an SNA.

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• Complex systems
• Optical chaos
• Laser dynamics
• Solid state lasers
• Chaos & nonlinear dynamics
• Fractal analysis