Wang Mingjin, Wang Feifan, Chen Jingxuan, Liu Wenzhen, Si Jiahao, Xu Yuanbo, Zhang Zheng, Chen Zihao, Peng Chao, Zheng Wanhua
A Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, CAS, Beijing 100083, China.
State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, CAS, Beijing 100083, China.
ACS Nano. 2024 Jul 23;18(29):18880-18888. doi: 10.1021/acsnano.3c09793. Epub 2024 Jul 11.
Emitting light toward on-demand directions is important for various optoelectronic applications, such as optical communication, displaying, and ranging. However, almost all existing directional emitters are assemblies of passive optical antennae and external light sources, which are usually bulky and fragile and show unendurable loss of light power. Here we theoretically propose and experimentally demonstrate a conceptual design of a directional emitter, by using a single surface-emitting laser source itself to achieve dynamically controlled beam steering. The laser is built on photonic crystals that operate near the band edges in the continuum. By shrinking laser sizes to tens-of-wavelength, the optical modes quantize in three-dimensional momentum space, and each of them directionally radiates toward the far-field. Further utilizing the luminescence spectrum shifting effect under current injection, we consecutively select a sequence of modes into lasing action and show the laser maintaining single-mode operation with line widths at a minimum of 1.8 MHz and an emitting power of ∼10 milliwatts, and we demonstrate fast beam steering across a range of 3.2° × 4° on a time scale of 500 ns. Our work proposes a method for on-chip active beam steering for the development of automotive, industrial, and robotic applications.
向按需方向发光对于各种光电应用非常重要，如光通信、显示和测距。然而，几乎所有现有的定向发射器都是无源光学天线和外部光源的组件，它们通常体积庞大且易碎，并且光功率损耗难以承受。在此，我们从理论上提出并通过实验证明了一种定向发射器的概念设计，即利用单个表面发射激光源本身来实现动态控制的光束转向。该激光器基于在连续谱带边缘附近工作的光子晶体构建。通过将激光器尺寸缩小到几十波长，光学模式在三维动量空间中量子化，并且它们中的每一个都向远场定向辐射。进一步利用电流注入下的发光光谱移动效应，我们连续选择一系列模式进入激光作用，并展示了该激光器保持单模运行，线宽最小为1.8 MHz，发射功率约为10毫瓦，并且我们在500 ns的时间尺度上展示了在3.2°×4°范围内的快速光束转向。我们的工作提出了一种用于片上有源光束转向的方法，以推动汽车、工业和机器人应用的发展。
