Jin Feng, Mandal Subhaskar, Wu Jinqi, Zhang Zhenhan, Wen Wen, Ren Jiahao, Zhang Baile, Liew Timothy C H, Xiong Qihua, Su Rui
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, Singapore.
Centre for Disruptive Photonic Technologies, Nanyang Technological University, 21 Nanyang Link, Singapore, Singapore.
Nat Commun. 2024 Dec 4;15(1):10563. doi: 10.1038/s41467-024-54658-4.
Topological exciton-polaritons are a burgeoning class of topological photonic systems distinguished by their hybrid nature as part-light, part-matter quasiparticles. Their further control over novel valley degree of freedom (DOF) has offered considerable potential for developing active topological optical devices towards information processing. Here, employing a two-dimensional (2D) valley-Hall perovskite lattice, we report the experimental observation of valley-polarized topological exciton-polaritons and their valley-dependent propagations at room temperature. The 2D valley-Hall perovskite lattice consists of two mutually inverted honeycomb lattices with broken inversion symmetry. By measuring their band structure with angle-resolved photoluminescence spectra, we experimentally verify the existence of valley-polarized polaritonic topological kink states with a large gap opening of ~ 9 meV in the bearded interface at room temperature. Moreover, these valley-polarized states exhibit counter-propagating behaviors under a resonant excitation at room temperature. Our results not only expand the landscape of realizing topological exciton-polaritons, but also pave the way for the development of topological valleytronic devices employing exciton-polaritons with valley DOF at room temperature.
拓扑激子极化激元是一类新兴的拓扑光子系统，其特点是具有光与物质的混合准粒子性质。它们对新型谷自由度（DOF）的进一步控制为开发用于信息处理的有源拓扑光学器件提供了巨大潜力。在此，我们利用二维（2D）谷霍尔钙钛矿晶格，报道了室温下谷极化拓扑激子极化激元及其谷依赖传播的实验观测结果。二维谷霍尔钙钛矿晶格由两个具有破缺反演对称性的相互倒置的蜂窝晶格组成。通过用角分辨光致发光光谱测量其能带结构，我们在室温下的胡须状界面中实验验证了具有约9 meV大带隙开口的谷极化极化激元拓扑扭结态的存在。此外，这些谷极化态在室温下的共振激发下表现出反向传播行为。我们的结果不仅拓展了实现拓扑激子极化激元的领域，也为在室温下开发采用具有谷自由度的激子极化激元的拓扑谷电子器件铺平了道路。
