Abstract
<title>Abstract</title> <p>Optical chaos is a powerful physical resource for secure communications, stochastic computing and photonic information processing owing to its intrinsic randomness and broadband dynamics. Among chaotic photonic platforms, Kerr microcomb-based sources are particularly attractive because they combine massive wavelength parallelism with broad spectral coverage, but the chaotic bandwidth of each comb tooth remains limited to the gigahertz scale by the cavity photon lifetime that governs the response speed of intracavity nonlinear dynamics. Here we develop a Vernier chaotic dual-microcomb platform in which multiheterodyne mapping reconstructs bandwidth-limited chaotic spectral elements into broadband radio-frequency (RF) chaos, thereby overcoming the single-tooth bandwidth bottleneck. The reconstructed RF chaotic bandwidth grows linearly with the number of mapped spectral-element pairs, thereby converting optical spectral parallelism into scalable electrical bandwidth. We experimentally generate RF chaotic states exceeding 40 GHz using only two mapped spectral-broadened spectral-element pairs, enabling single-channel offline random-bit generation at 3.072 Tbps and real-time extraction at 40 Gbps. Furthermore, the architecture offers a route towards controllable frequency translation and spectral tailoring of chaotic waveforms. These results establish Vernier chaotic microcombs as a platform for broadband chaos transduction and scalable RF-domain chaotic waveform synthesis.</p>