Smirnova Daria, Tripathi Aditya, Kruk Sergey, Hwang Min-Soo, Kim Ha-Reem, Park Hong-Gyu, Kivshar Yuri
Nonlinear Physics Center, Research School of Physics, Australian National University, Canberra, ACT 2601 Australia.
Institute of Applied Physics, Russian Academy of Science, Nizhny Novgorod, 603950 Russia.
Light Sci Appl. 2020 Jul 20;9:127. doi: 10.1038/s41377-020-00350-3. eCollection 2020.
The study of topological phases of light underpins a promising paradigm for engineering disorder-immune compact photonic devices with unusual properties. Combined with an optical gain, topological photonic structures provide a novel platform for micro- and nanoscale lasers, which could benefit from nontrivial band topology and spatially localized gap states. Here, we propose and demonstrate experimentally active nanophotonic topological cavities incorporating III-V semiconductor quantum wells as a gain medium in the structure. We observe room-temperature lasing with a narrow spectrum, high coherence, and threshold behaviour. The emitted beam hosts a singularity encoded by a triade cavity mode that resides in the bandgap of two interfaced valley-Hall periodic photonic lattices with opposite parity breaking. Our findings make a step towards topologically controlled ultrasmall light sources with nontrivial radiation characteristics.
光的拓扑相研究为设计具有异常特性的无序免疫紧凑型光子器件奠定了一个很有前景的范例。结合光学增益，拓扑光子结构为微纳尺度激光器提供了一个新颖的平台，这类激光器可受益于非平凡能带拓扑和空间局域化能隙态。在此，我们提出并通过实验证明了有源纳米光子拓扑腔，该拓扑腔将III-V族半导体量子阱作为结构中的增益介质。我们观察到了具有窄光谱、高相干性和阈值行为的室温激光发射。发射光束具有由三重简并腔模编码的奇点，该模位于两个具有相反宇称破缺的界面谷霍尔周期光子晶格的带隙中。我们的研究结果朝着具有非平凡辐射特性的拓扑控制超小光源迈出了一步。
