论文标题
宽带等离子体隔离器与低甲状腺素磁光材料兼容
Broad-band plasmonic isolator compatible with low-gyrotropy magneto-optical material
论文作者
论文摘要
尽管研究了数十年，但光学隔离器仍然是光子综合电路的主要缺失元素之一。到目前为止，最好的解决方案是基于横向磁光效应，使用窄带谐振器或高兼副磁光材料，在通常的光子平台上很难集成。我们在本文中提出了一个彻底的新概念，即使在低甲状腺素材料的情况下，也能够执行宽带的非转向传播。该原理探索了由于磁性 - 双质效应，即，在血浆插槽波导中诱导的耦合模式不对称性，探索了来回光路的分离。我们在数字上表明，这种金属-MO介电 - 金属插槽波导与合适的侧耦合损耗的矩形纳米腔相结合，在几十纳米的带宽上可提供18 dB的隔离率，只有2 dB插入损失。我们提出了一种分析方法，描述了这种磁质 - 插槽波导，以识别所涉及的物理机制和隔离器的优化规则。此外，我们表明，可以考虑使用易于综合的混合材料或复合材料的新型集成隔离器的隔离率，以隔离率低至20 dB，可以考虑使用低甲状腺素材料（降至〜0.005）。
Optical isolator remains one of the main missing elements for photonic integrated circuits despite several decades of research. The best solutions up to now are based on transverse magneto-optical effect using either narrow-band resonators or high-gyrotropy magneto-optical materials with difficult integration on usual photonic platforms. We propose in this paper a radically new concept which enables performing broad-band non-reciprocal transmission even in the case of low-gyrotropy material. The principle explores the separation of back and forth light paths, due to the magneto-biplasmonic effect, i.e., the coupled mode asymmetry induced in plasmonic slot waveguides loaded with a magneto-optical (MO) layer. We show numerically that such a metal-MO dielectric-metal slot waveguide combined with suitable side-coupled lossy rectangular nanocavities gives more than 18 dB isolation ratio on several tens of nanometers bandwidth, with only 2 dB insertion losses. We propose an analytical approach describing such a magneto-plasmonic slot waveguide to identify the involved physical mechanisms and the optimization rules of the isolator. Additionally, we show that low-gyrotropy material (down to ~0.005) can be considered for isolation ratio up to 20 dB, opening the road to a new class of integrated isolators using easy-to-integrate hybrid or composite materials.
