Graphene patterned into plasmonic structures like ribbons or discs strongly increases the linear and nonlinear optical interaction at resonance. The nonlinear optical response is governed by hot carriers, leading to a red-shift of the plasmon frequency. In magnetic fields, the plasmon hybridizes with the cyclotron resonance, resulting in a splitting of the plasmonic absorption into two branches. Here we present how this splitting can be exploited to tune the nonlinear optical response of graphene discs. In the absence of a magnetic field, a strong pump-induced increase in on-resonant transmission can be observed, but fields in the range of 3 T can change the characteristics completely, leading to an inverted nonlinearity. A two temperature model is provided that describes the observed behavior well.

石墨化成带状或盘状等离激元结构的图形可以大大增加共振时的线性和非线性光学相互作用。非线性光学响应受热载流子控制，导致等离激元频率发生红移。在磁场中，等离激元与回旋共振杂交，导致等离激元吸收分裂为两个分支。在这里，我们介绍如何利用这种分裂来调节石墨烯圆盘的非线性光学响应。在没有磁场的情况下，可以观察到泵激引起的共振传输的强烈增加，但是在3 T范围内的场可以完全改变特性，从而导致反向非线性。提供了两个温度模型，可以很好地描述观察到的行为。