Nanowire photonic crystal surface-emitting lasers (PCSELs)

光子晶体表面发射激光器(PCSEL)的最新发展已经显示出优于常用的垂直腔面发射激光器(VCSEL)和边缘发射激光器的性能。高亮度的对称光束和极窄的光束发散使其在光探测和测距(Lidar)和光学传感应用中具有极大的前景。通常，形成光子晶格的自上而下的刻蚀和外延过度生长工艺相结合来制造PCSEL。在这个项目中，我们将利用加的夫大学金属有机化学气相沉积(MOCVD)所开发的InGaAs纳米线平台用于PCSEL应用。这些纳米线是使用无催化剂选择性异质外延在光刻定义的图案化SOI衬底上生长的。硅和III-V纳米线之间的纳米级界面有利于横向的弹性松弛，克服了材料集成中最艰巨的挑战之一。将纳米线排列成光子晶体结构并设计纳米线阵列参数(例如晶格常数、纳米线直径、高度)以匹配光学模式的能力为带边激光器和拓扑激光器等新兴技术创造了令人兴奋的机会。这位受资助的学生预计将专注于纳米线光子晶体结构的设计、外延和特征，并得到建模和制造方面的博士后研究人员和合作者的支持。

Recent developments in photonic crystal surface-emitting lasers (PCSELs) have shown superior performance to commonly used vertical cavity surface emitting lasers (VCSELs) and edge emitting lasers. The high-brightness, symmetric beam with extremely narrow beam divergence make them highly promising for light detection and ranging (Lidar) and optical sensing applications. Typically, top-down etching to form photonic crystal lattices and epitaxial overgrowth processes are combined to fabricate PCSELs. In this project, we will make use of the InGaAs nanowire platform developed by the metal organic chemical vapour deposition (MOCVD) at Cardiff University for PCSEL applications. These nanowires are grown on lithographically defined, patterned SOI substrates using catalyst-free selective hetero-epitaxy. The nanoscale interface between silicon and III-V nanowires facilitates elastic relaxation in lateral directions, overcoming one of the most formidable challenges in materials integration. The ability to arrange nanowires into photonic crystal structures and to engineer the nanowire array parameters (e.g. lattice constant, nanowire diameter, height) to match optical modes creates exciting opportunities for emerging technologies such as band-edge lasers and topological lasers. The funded student is expected to be focusing on design, epitaxy and characterisations of nanowire photonic crystal structures, with support from postdoc researchers and collaborators on modelling and fabrication.