Topological phase induced by distinguishing parameter regimes in a cavity optomechanical system with multiple mechanical resonators

Abstract

We propose two kinds of distinguishing parameter regimes to induce a topological Su-Schrieffer-Heeger (SSH) phase in a one-dimensional (1D) multiresonator cavity optomechanical system via modulation of the frequencies of both cavity fields and resonators. The introduction of frequency modulations allows us to eliminate the Stokes heating process for mapping of the tight-binding Hamiltonian without the usual rotating-wave approximation, which is totally different from the traditional mapping of the topological tight-binding model. We find that the tight-binding Hamiltonian can be mapped into a topological SSH phase via modification of the Bessel function originating from the frequency modulations of cavity fields and resonators, and the induced SSH phase is independent of the effective optomechanical coupling strength. On the other hand, the insensitivity of the system to the effective optomechanical coupling provides us another new path to induce the topological SSH phase based on the present 1D cavity optomechanical system. And we show that the system can exhibit a topological SSH phase via variation of the effective optomechanical coupling strength in an alternative way, which is much easier to achieve in experiments. Furthermore, we also construct an analogous bosonic Kitaev model with trivial topology by keeping the Stokes heating processes. Our scheme provides a steerable platform for investigation of the effects of next-nearest-neighbor interactions on the topology of the system.