Non-Hermitian-enhanced topological protection of chaotic dynamics in one-dimensional optomechanics lattice

Abstract

Chaotic dynamics in microcavity have promoted massive discoveries and applications ranging from decoherence suppression to broadband optical devices. However, a chaotic light source on the chip is more likely to suffer from the ambient randomness and perturbations than its bulk counterparts, vanishing chaotic dynamics. Topological protection provides a robust framework for manipulating the periodic wave dynamics, whereas the symmetric layout in topological protection poses a direct challenge to leveraging this notion in chaotic dynamics. Here, we discover that benefiting from an engineered exceptional point, the non-Hermitian-enhanced topological protection yields zero modes and switches the chaotic dynamics. As a result, this new effect significantly extends the topologically protected chaotic dynamics to a more general trivial phase beyond the constraint of the topological invariant. More importantly, the zero modes merit robust chaotic dynamics prevail with intentionally introduced perturbations. Moreover, we find that an extended photonics lattice composed of an increased number of microcavities not only offers a more robust topological protection but also can delay the chaos generation, providing a new degree of freedom to harness the chaos generation. This study presents a promising approach for robust on-chip chaotic light sources and advances various explorations on multibody non-Hermitian physics.