Institut für Angewandte Physik, Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany.
Opt Lett. 2011 May 1;36(9):1533-5. doi: 10.1364/OL.36.001533.
Previous second-harmonic-generation experiments on metallic split-ring-resonator arrays have been performed at fixed fundamental laser center frequency. Here, we perform nonlinear optical spectroscopy on a first set of samples, revealing pronounced resonances. Furthermore, to clarify the role of higher-order split-ring resonances, we perform additional experiments on a second set of samples in which the fundamental split-ring-resonator resonance frequencies are lithographically tuned, whereas the higher-order resonances are fixed. We find that the higher-order resonances merely reabsorb the second-harmonic generation, revealing the fundamental split-ring resonance as the nonlinear source.
先前关于金属分环谐振器阵列的二次谐波产生实验是在固定的基本激光中心频率下进行的。在这里，我们对一组样品进行了非线性光学光谱测量，揭示了明显的共振。此外，为了澄清高阶分环共振的作用，我们在第二组样品上进行了额外的实验，其中基本分环谐振器共振频率通过光刻进行调整，而高阶共振保持不变。我们发现高阶共振仅重新吸收二次谐波产生，揭示了基本分环共振是非线性源。
