论文标题
在平面光照明下单个硅磁盘中高阶斜臂的实验性观察
Experimental observation of higher-order anapoles in individual silicon disks under in-plane illumination
论文作者
论文摘要
Anapole状态（以强烈抑制远场散射为特征）自然出现在高索引纳米粒子中，这是由于某些多极矩之间的干扰。最近，由于电芯片光子学的要求，在平面照明下表征了一阶电anapole，这是由于电和环形偶极子之间的干扰而产生的。在这里，我们迈出了进一步的一步，并报告了在平面内照明下单个硅磁盘中高阶（磁性和二阶电）阿位状态的观察。为此，我们增加了磁盘尺寸（半径和厚度），以便在电信波长处出现此类Anapoles。实验表明，垂直于磁盘平面的远场散射在预期波长和所选的极化下倾角，我们将其解释为高阶anapoles的标志。讨论了正常和面内激发之间的一些差异，特别是笛卡尔电气和环形矩的总和不进行平面内发生率。我们的结果铺平了在光子综合电路中使用不同Anapole态的方式，无论是在硅还是其他高索引介电材料上。
Anapole states - characterized by a strong suppression of far-field scattering - naturally arise in high-index nanoparticles as a result of the interference between certain multipolar moments. Recently, the first-order electric anapole, resulting from the interference between the electric and toroidal dipoles, was characterized under in-plane illumination as required in on-chip photonics. Here, we go a step further and report on the observation of higher-order (magnetic and second-order electric) anapole states in individual silicon disks under in-plane illumination. To do so, we increase the disk dimensions (radius and thickness) so that such anapoles occur at telecom wavelengths. Experiments show dips in the far-field scattering perpendicular to the disk plane at the expected wavelengths and the selected polarizations, which we interpret as a signature of high-order anapoles. Some differences between normal and in-plane excitation are discussed, in particular the non-cancellation of the sum of the Cartesian electric and toroidal moments for in-plane incidence. Our results pave the way towards the use of different anapole states in photonic integrated circuits, either on silicon or other high-index dielectric materials.
