Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
Institut für Theoretische Festkörperphysik, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
Nat Commun. 2014 Apr 28;5:3730. doi: 10.1038/ncomms4730.
The field of metamaterial research revolves around the idea of creating artificial media that interact with light in a way unknown from naturally occurring materials. This is commonly achieved using sub-wavelength lattices of electronic or plasmonic structures, so-called meta-atoms. One of the ultimate goals for these tailored media is the ability to control their properties in situ. Here we show that superconducting quantum interference devices can be used as fast, switchable meta-atoms. We find that their intrinsic nonlinearity leads to simultaneously stable dynamic states, each of which is associated with a different value and sign of the magnetic susceptibility in the microwave domain. Moreover, we demonstrate that it is possible to switch between these states by applying nanosecond-long pulses in addition to the microwave-probe signal. Apart from potential applications for this all-optical metamaterial switch, the results suggest that multistability can also be utilized in other types of nonlinear meta-atoms.
超材料研究领域围绕着创造与光相互作用的人工介质的理念展开，这种相互作用的方式是自然界材料所不具备的。这通常可以通过电子或等离子体结构的亚波长晶格，即所谓的“元原子”来实现。这些定制介质的最终目标之一是能够现场控制其性能。在这里，我们展示了超导量子干涉器件可以用作快速、可切换的元原子。我们发现，它们的固有非线性导致同时存在稳定的动态状态，每个状态都与微波域中不同的磁导率值和符号相关。此外，我们还证明，除了微波探针信号之外，还可以通过施加纳秒长的脉冲来在这些状态之间进行切换。除了这种全光超材料开关的潜在应用之外，这些结果还表明，多稳定性也可以在其他类型的非线性元原子中得到利用。
