Phonon Polaritons in Twisted Double-Layers of Hyperbolic van der Waals Crystals
Phonon Polaritons in Twisted Double-Layers of Hyperbolic van der Waals Crystals
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双曲范德华晶体扭曲双层中的声子极化子
DOI：
10.1021/acs.nanolett.0c01627
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发表时间：
2020
期刊：
影响因子：
10.8
通讯作者：
Deng Shaozhi
中科院分区：
文献类型：
--
作者：
Zheng Zebo;Sun Fengsheng;Huang Wuchao;Jiang Jingyao;Zhan Runze;Ke Yanlin;Chen Huanjun;Deng Shaozhi
控制两个堆叠的货车德瓦耳斯（vdW）晶体之间的扭转角是调节其电子和光子性质的强有力的方法。双曲介质最近吸引了很多关注，由于他们的能力，定制电磁波在亚波长尺度，然而，通常需要复杂的图案化程序。在这里，我们展示了一种无光刻的方法来操纵双曲性，通过利用声子极化激元的扭曲依赖耦合的双层vdW α-MoO 3，一种天然的双轴双曲晶体。由于这种层间耦合，可以修改极化激元等离子体轮廓，从而允许通过调节两层之间的取向角来控制极化激元特性。我们的研究结果提供了机会，控制纳米级的光流与扭曲堆叠的VDW晶体。
Controlling the twist angle between two stacked van der Waals (vdW) crystals is a powerful approach for tuning their electronic and photonic properties. Hyperbolic media have recently attracted much attention due to their ability to tailor electromagnetic waves at the subwavelength-scale which, however, usually requires complex patterning procedures. Here, we demonstrate a lithography-free approach for manipulating the hyperbolicity by harnessing the twist-dependent coupling of phonon polaritons in double-layers of vdW α-MoO3, a naturally biaxial hyperbolic crystal. The polariton isofrequency contours can be modified due to this interlayer coupling, allowing for controlling the polaritonic characteristics by adjusting the orientation angles between the two layers. Our findings provide opportunities for control of nanoscale light flow with twisted stacks of vdW crystals.