Chen Na, Teng Hanchao, Hu Hai, Liu Min, Jiang Chengyu, Xue Zhuoxin, Zhu Hualong, Gui Jiayi, Li Peining, Alù Andrea, Dai Qing
CAS Key Laboratory of Nanophotonic Materials and Devices, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing, P. R. China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, P. R. China.
Nat Mater. 2025 Jul 31. doi: 10.1038/s41563-025-02280-0.
Hyperbolic polaritons facilitate nanoscale light manipulation, but strong field confinement limits their transmission across interfaces. Conversely, leaky waves can convert radiation from confined sources towards the far field. Here we combine hyperbolic polaritons and leaky wave radiation to demonstrate flatland leaky polaritonic wakes. We employ a mixed-dimensional van der Waals heterostructure consisting of a nanoscale waveguide strip on a van der Waals film. The waveguide mode, confined inside the hyperbolic light cone of the background film, enables efficient directional in-plane emission of fast phonon polaritons. The constructive interference of these leaky polaritons generates highly directional polaritonic wakes. Their spatial symmetry can be tailored through the orientation of the heterostructure with respect to the hyperbolic film dispersion. Leveraging van der Waals stacking, we also demonstrate effective acceleration and deceleration of polaritonic wakes by locally tailoring the leaky nano-waveguide dispersion through gradient thickness design. Our findings demonstrate that polaritonic wakes hold promise for integrated nanophotonic circuits.
双曲线极化激元有助于纳米级光操控，但强场限制会限制它们在界面间的传输。相反，泄漏波可以将受限源的辐射转换为远场辐射。在此，我们将双曲线极化激元与泄漏波辐射相结合，展示了平面泄漏极化激元尾迹。我们采用了一种混合维度的范德瓦尔斯异质结构，它由范德瓦尔斯薄膜上的纳米级波导条组成。被限制在背景薄膜双曲线光锥内的波导模式，能够实现快速声子极化激元的高效定向面内发射。这些泄漏极化激元的相长干涉产生了高度定向的极化激元尾迹。它们的空间对称性可以通过异质结构相对于双曲线薄膜色散的取向来调整。利用范德瓦尔斯堆叠，我们还通过梯度厚度设计局部调整泄漏纳米波导色散，展示了极化激元尾迹的有效加速和减速。我们的研究结果表明，极化激元尾迹在集成纳米光子电路方面具有潜力。
