Chiral Chaos Enhanced Sensing

Abstract: Chirality refers to the property that an object and its mirror image cannot overlap each other by spatial rotation and translation, and can be found in various research fields. We here propose chiral chaos and construct a chiral chaotic device via coupled whispering gallery mode resonators, where routes to chaos exhibit pronounced chirality for two opposite pumping directions. The mechanism responsible for this phenomenon is that time-reversal symmetry of the traveling-wave light fields is broken by the Rayleigh scatterers inserted in resonators. Combining with the Lyapunov exponents, we propose metrics to measure the symmetry and chirality between different chaotic dynamics. We find that such a chiral chaotic device can be applied to achieve sensing with high sensitivity, wide detectable range, and strong robustness to the phase and orientation randomness of weak signals. Our work presents a promising candidate for on-chip sensing and may have applications in quantum networks and chaotic communications.