Tunable anti–parity-time-symmetric chaos in optomechanics

The chaotic light source is one of the most crucial foundations in optical physics studies and photonic devices. The microcavity provides the predominant solution of compact chaotic light sources in integrated photonics. Still, its prefixed feature has severely ruled out access to tuning for meeting the ever-increasing demands of the general-purpose chaotic light source in engineering. Here we report a demonstration of a chaotic light source with a switchable bandpass--band-stop chaotic emission and tunable bandwidth in a spinning microcavity anti-parity-time (anti-$\mathcal{PT}$). system. In addition, the arrangement of anti-$\mathcal{PT}$ microcavity presents several phenomena such as loss-induced chaotic emission and two different chaotic emissions from one microcavity light source. Such advantages offer another possible way to advance multiplex photonic devices and on-chip chaotic light source fabrication. These results provide a promising approach for the tunable chaotic source and serve as tools for applications in secure communications, electromechanical switching, and exploring non-Hermitian physics.