Development of Semiconductor Lasers with Microcavity and Quantum Wires

对于21世纪具有超高信道容量的超高速光网络系统来说，开发适合于时间轴和空间轴高度集成的光源是必不可少的。因此，建立下一代新型半导体激光器是迫切需要的。本文首次制备了具有垂直微腔结构的应变InGaAs量子线激光器。量子线和量子点是高效半导体激光器的重要组成部分。在这种激光结构中，采用选择性金属有机化学气相沉积（MOCVD）技术生长出横向宽度约为10nm的量子线。微腔长度为41 (1=883nm)，具有AlAs/AlGaAs分布的Bragg反射体。通过测量微腔和无微腔的光致发光，证明了微腔效应的存在。在77K光泵浦下观察到激光振荡。在本研究项目中，我们还研究了微腔量子点激光器。为此，我们首先研究了使用自组装生长技术制备InGaAs/GaAs量子点的技术。量子点的尺寸约为15纳米。我们成功地制造了一个垂直腔的量子点激光结构。这些结果对21世纪半导体激光技术的发展具有重要意义。

For the ultra-high speed optical network system with ultra-high channel capacity in the 21th century, it is indispensable to develop light sources which are suitable for high integration with both the time-axis and the spatial axis. Therefore, new type of semiconductor lasers of the next generation strongly requested to be established.In this study a strained InGaAs quantum wire laser with a vertical microcavity structures was fabricated for the first time. Quantum wires and dots are important for highly efficient semiconductor lasers. In this laser structure, quantum wires with a lateral width of about 10nm were grown by a selective metal organic chemical vapor deposition (MOCVD) technique. The length of the microcavity was 41 (1=883nm), with AlAs/AlGaAs distributed Bragg reflectors. The microcavity effect was demonstrated by the measurement of photoluminescence with and without the cavity. Lasing oscillation was observed at 77K by optical pumping.In this research program, we also investigated the microcavity quantum dot lasers. For this purpose, we first investigated fabrication technology for the InGaAs/GaAs quantum dots using the self-assembling growth technique. The size of the quantum dots is around 15nm. We succeeded in fabricating a vertical cavity quantum dot laser structures.These results are quite useful for establishing semiconductor laser technology for the 21th century.