We theoretically demonstrate a kind of plasmon coupled cavity to achieve a nanolaser with high intensity and low threshold. The plasmon cavity is composed of the gold film substrate and gold disk array, which supports two strong coupled resonance modes (i.e. surface plasmon polariton (SPP) and localized surface plasmon (LSP)). Compared with the nanolaser with the LSP resonance structure, the scattering cross-section of the LSP-SPP coupled laser is 80 times higher. The coupled cavity nanolaser with different wavelengths can be excited with different plasmon resonance modes by selecting the appropriate gain medium. In addition, a compact tunable dual-wavelength laser can be developed using this coupled structure.

中文翻译：

---

基于局部和传播表面等离子体激元的强耦合的双波长纳米激光

我们从理论上证明了一种等离激元耦合腔，以实现具有高强度和低阈值的纳米激光。等离子体腔由金膜衬底和金盘阵列组成，该阵列支持两种强耦合共振模式（即表面等离子体激元（SPP）和局部表面等离子体激元（LSP））。与具有LSP共振结构的纳米激光器相比，LSP-SPP耦合激光器的散射截面高80倍。通过选择适当的增益介质，可以用不同的等离子体共振模式激发具有不同波长的耦合腔纳米激光器。另外，使用这种耦合结构可以开发出紧凑的可调谐双波长激光器。