论文标题
石墨烯谐振器中的对称性诱导频率梳子
Symmetry-breaking induced frequency combs in graphene resonators
论文作者
论文摘要
非线性是二维材料动力学固有的。像世代相传耦合之类的现象已经出现在只有几纳米的振幅上，并且仍在等待一系列未开发的效果。在这里，我们演示了一种在具有对称性力的石墨烯谐振器中生成机械频率梳子的途径。我们使用静电力打破膜的平面对称性，并将其共振频率调整为两对一的内部共振，从而在其两种机械模式之间实现了强耦合。当提高驱动水平时，我们会观察到基本共振峰的分裂，然后观察到频率梳状态的出现。我们将观察到的物理学归因于非对称恢复潜力，并表明频率梳状态是由周期溶液的Neimark分叉介导的。这些结果表明，由于对称性破坏，2D材料谐振器中的机械频率梳子和混沌动力学可以在内部共振附近出现。
Nonlinearities are inherent to the dynamics of two-dimensional materials. Phenomena like intermodal coupling already arise at amplitudes of only a few nanometers, and a range of unexplored effects still awaits to be harnessed. Here, we demonstrate a route for generating mechanical frequency combs in graphene resonators undergoing symmetry-breaking forces. We use electrostatic force to break the membrane's out-of-plane symmetry and tune its resonance frequency towards a two-to-one internal resonance, thus achieving strong coupling between two of its mechanical modes. When increasing the drive level, we observe splitting of the fundamental resonance peak, followed by the emergence of a frequency comb regime. We attribute the observed physics to a non-symmetric restoring potential, and show that the frequency comb regime is mediated by a Neimark bifurcation of the periodic solution. These results demonstrate that mechanical frequency combs and chaotic dynamics in 2D material resonators can emerge near internal resonances due to symmetry-breaking.
