The non-linear responses of optical materials offer useful mechanisms for optical switching, novel optical sources, and harmonic frequency conversion. However, the non-linear response of traditional materials is usually extremely weak and requires high input power for excitation. In this study, we theoretically propose a scheme for enhancing the third harmonic generation (THG) efficiency and output power of layered graphene disks array by introducing a plasmonic antibonding state with enhanced oscillation strength due to plasmonic coupling. We verify that, the THG efficiency of a double-layer stacked graphene/SiO₂ disk structure under relatively low input intensity can be significantly enhanced more than one order of magnitude with appropriate design, as compared with monolayer patterned graphene nanostructure. We also demonstrate that the THG efficiency can be further improved by optimizing the geometry parameters such as spacer distance and Fermi energy. Our results offer an effective mechanism for significantly improving THG efficiency in the mid-infrared and terahertz ranges, thereby paving the way for new frequency converters and modulators in optical communication and signal processing.

光学材料的非线性响应为光学切换，新型光源和谐波频率转换提供了有用的机制。但是，传统材料的非线性响应通常非常弱，并且需要高输入功率来激发。在这项研究中，我们从理论上提出了一种方案，该方案通过引入由于等离子体耦合引起的振荡强度增强的等离子体反键合状态来提高层状石墨烯磁盘阵列的三次谐波产生（THG）效率和输出功率。我们验证了双层堆叠石墨烯/ SiO ₂的THG效率与单层图案化的石墨烯纳米结构相比，采用适当的设计，可以在相对较低的输入强度下将光盘结构显着增强一个数量级以上。我们还证明，通过优化几何参数（如间隔距离和费米能量）可以进一步提高THG效率。我们的结果为有效提高中红外和太赫兹范围内的THG效率提供了有效的机制，从而为光通信和信号处理中的新型变频器和调制器铺平了道路。