Centre for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Nat Commun. 2023 Mar 15;14(1):1433. doi: 10.1038/s41467-023-36963-6.
Various topological laser concepts have recently enabled the demonstration of robust light-emitting devices that are immune to structural deformations and tolerant to fabrication imperfections. Current realizations of photonic cavities with topological boundaries are often limited by outcoupling issues or poor directionality and require complex design and fabrication that hinder operation at small wavelengths. Here we propose a topological cavity design based on interface states between two one-dimensional photonic crystals with distinct Zak phases. Using a few monolayers of solution-processed all-inorganic cesium lead halide perovskite quantum dots as the ultrathin gain medium, we demonstrate a lithography-free, vertical-emitting, low-threshold, and single-mode laser emitting in the green. We show that the topological laser, akin to vertical-cavity surface-emitting lasers (VCSELs), is robust against local perturbations of the multilayer structure. We argue that the design simplicity and reduction of the gain medium thickness enabled by the topological cavity make this architecture suitable for low-cost and efficient quantum dot vertical emitting lasers operating across the visible spectral region.
最近，各种拓扑激光概念已经能够实现对结构变形具有鲁棒性且对制造缺陷具有容忍性的发光器件。目前具有拓扑边界的光子腔的实现往往受到出耦合问题或较差的方向性的限制，并且需要复杂的设计和制造，这阻碍了在小波长下的操作。在这里，我们提出了一种基于具有不同 Zak 相位的一维光子晶体之间的界面态的拓扑腔设计。使用几层溶液处理的全无机铯铅卤钙钛矿量子点作为超薄增益介质，我们展示了一种无光刻、垂直发射、低阈值、单模激光，在绿光中发射。我们表明，拓扑激光类似于垂直腔面发射激光器 (VCSEL)，对多层结构的局部扰动具有鲁棒性。我们认为，拓扑腔设计的简单性和增益介质厚度的减少使这种结构适合于低成本和高效率的量子点垂直发射激光器，可在整个可见光谱区域工作。
