Opt Express. 2023 Feb 27;31(5):8704-8713. doi: 10.1364/OE.473449.
Networks of semiconductor lasers are the foundation of numerous applications and fundamental investigations in nonlinear dynamics, material processing, lighting, and information processing. However, making the usually narrowband semiconductor lasers within the network interact requires both high spectral homogeneity and a fitting coupling concept. Here, we report how we use diffractive optics in an external cavity to experimentally couple vertical-cavity surface-emitting lasers (VCSELs) in a 5×5 array. Out of the 25 lasers, we succeed to spectrally align 22, all of which we lock simultaneously to an external drive laser. Furthermore, we show the considerable coupling interactions between the lasers of the array. This way, we present the largest network of optically coupled semiconductor lasers reported so far and the first detailed characterization of such a diffractively coupled system. Due to the high homogeneity of the lasers, the strong interaction between them, and the scalability of the coupling approach, our VCSEL network is a promising platform for experimental investigations of complex systems, and it has direct applications as a photonic neural network.
半导体激光器网络是许多应用和非线性动力学、材料处理、照明和信息处理等基础研究的基础。然而，要使网络中通常的窄带半导体激光器相互作用，需要高光谱同质性和合适的耦合概念。在这里，我们报告了如何在外部腔中使用衍射光学来实验性地耦合垂直腔面发射激光器（VCSEL）的 5×5 阵列。在 25 个激光器中，我们成功地对 22 个进行了光谱对准，所有这些激光器都同时被锁定到外部驱动激光器上。此外，我们还展示了该阵列中激光器之间的相当大的耦合相互作用。通过这种方式，我们展示了迄今为止报道的最大的光耦合半导体激光器网络，以及对这种衍射耦合系统的首次详细特征描述。由于激光器的高同质性、它们之间的强相互作用以及耦合方法的可扩展性，我们的 VCSEL 网络是研究复杂系统的实验的有前途的平台，并且它在光子神经网络中具有直接的应用。
