Abstract
Growing interest in integrated optical communications and data processing applications drives the development of ultra-small and energy efficient on-chip photonic components. High performance small footprint laser integrated on silicon is one of the key ingredients in this scheme. As a part of an entire photonic crystal platform for realizing components with required functionalities, lasers based on photonic crystal cavities stand out as rapidly progressing technology. Majority of demonstrations utilize photonic crystal lasers where the active material is extending across the entire device region. Such structure is far from optimal as heating and absence of carrier confinement degrade device characteristics. The buried heterostructure concept, which is wellknown in semiconductor lasers technology, can be implemented with the photonic crystals and address the critical requirements for on-chip applications: device operating speed, output power and energy consumption. This thesis is focused on the development of buried heterostructure photonic crystal lasers. Critically important material etching and re-growth processes are analysed in detail to increase understanding of involved physical mechanisms. The feasibility and limitations of accurate alignment between formed buried heterostructure regions and photonic crystal cavities are addressed by studying fabrication process-induced distortion of bonded InP-on-Si wafers. Combined all together, high performance optically-pumped photonic crystal cavity lasers with embedded quantum wells active material are realized. Among them the single- and multi-mode buried heterostructure Fano lasers are demonstrated for the first time ever. The buried heterostructure photonic crystal lasers on Si platform promise exciting opportunities in the future for novel device design demonstrations as well as for photonic integrated circuits applications.
Info
Thesis PhD, 2019
UN SDG Classification
DK Main Research Area
Science/Technology
